Join us for an evening/night mountain bike ride through Limestone Canyon Nature Preserve and Red Rock Wilderness, part of OCParks’ Irvine Ranch Open Space. We will ride approximately 12 miles, with 1500′ of climbing along a variety singletrack trails and ranch roads. The route will vary based on trail conditions/availability.

This ride is not recommended as a first time night ride. Bring adequate lights, a jacket, plenty of water, spare tubes, tools and all other equipment to be self-sufficient on the trails. Hopefully we will see some of our local nocturnal critters. Motorized recreation vehicles of any class or type are not permitted for use in the Nature Preserve.

Please note that you will be asked to adhere to the following measures during the activity in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-4 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register for Limestone and Red Rock Night Ride.

Join us for a fitness-focused hike on the paved Hicks Haul Road in the Irvine Open Space Preserve. During the spring, summer and fall, hikers will enjoy wonderful sunset views and a panoramic overview of Orange County. This hike travels about 3.5 miles, up to the top of Loma Ridge and back down. The hike is conducted at about 3-3.5 miles per hour, but you may travel a bit faster or slower, at a walk, run, or jog depending on your comfort level. Most participants finish the route in about 1 hour. Because of the paved surface of the road, you may wear regular running or walking shoes. Trail shoes are fine, but not required. Please bring adequate water and a red-tinted flashlight as the return portion of the hike may be after sunset.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-3 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering. To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page.

Learn more and register for After Work Fitness Hike on Paved Hicks Haul Road.

Join us for a strenuous, extremely challenging, fast-paced cardio hike in Weir Canyon that leads us on a figure eight-shaped route. Along the way we’ll be rewarded with stunning panoramic views of Weir Canyon, Gypsum Canyon, Fremont Canyon, and Blind Canyon. On a clear day it is possible to see Catalina Island, Mount Baldy, and even Downtown LA. Wildlife sightings are possible, too.

This is an advanced 9.5 mile cardio hike, completed in less than 3 hours and includes 1600 ft of elevation gain. This hike is for experienced, physically fit hikers who enjoy the challenge of multiple steep climbs and descents. There are no rest stops and the average 3.5 mile per hour fast-pace can be extremely difficult over steep terrain in the wilderness setting.

Please bring a minimum of 70 oz. water and trail snacks. Come prepared with a pack, sturdy closed-toe hiking shoes or boots, sunscreen, first aid, and all other supplies to keep you safe and healthy on the trail for the extreme fast-paced hike in a wilderness area. Each participant must carry his or her own pack and water. Under-prepared participants may be denied access to this program.

Please note that you will be asked to adhere to the following measures during the activity in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-4 activity on the land.

Learn more and register for After Work Cardio Hike in Weir Canyon: Weir(d) Eight.

Ready for a workout? Forget the gym for the day and head outside! Join us for an exhilarating morning fitness hike on the paved Hicks Haul Road in OC Parks’ Irvine Ranch Open Space. This hike allows you to choose between a 3, 6, or 8 mile route, all of which are conducted at the speed of about 3.0 to 3.5 miles per hour. The footing on the asphalt paved road is smoother than dirt roads and single track trails normally found in Limestone Canyon Nature Preserve, but is beginning to show its age with cracks, crevices and an occasional dip. Otherwise, the terrain is smooth, so this is a great walk for anyone who wants a “wilderness experience” without getting dirty! The 6 and 8 mile routes experience two fairly steep ascents and descents. The 3 mile route takes you to the top of Loma Ridge and back down. Along the way, you will have sweeping views of much of Orange County and the Santa Ana Mountains. Various animals, like hawks, deer, and lizards are also frequently seen in this area.

Participants should be confident in their ability to hike 3, 6, or 8 miles at a steady pace. Please come prepared with proper hiking attire, ample water and adequate sun protection. Because of the paved surface, you may wear walking or running shoes instead of hiking boots. For the longer distances, at least 2 quarts of water (64 oz) is recommended. Ages 16 and up.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-3 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register for Tuesday Morning Fitness Hike on Paved Hicks Haul Road.

Limestone Canyon is a treasure waiting to be discovered. Join us for an afternoon, fast paced, 5.5-mile fitness hike with 750 ft of elevation. The hike will be a great introduction to fitness, cardio-style hikes as well as OC Parks’ magnificent Irvine Ranch Open Space.  Views of Limestone Canyon, and the surrounding wilderness, from Limestone Ridge will be the highlight of our tour.

Please bring a minimum of 48 oz. water. Come prepared with a pack, sturdy closed-toed hiking shoes or boots, sunscreen, first aid, and all other supplies to keep you safe and healthy on the trail for this hike in a wilderness area. Each participant must carry his or her own pack and water.  Under-prepared participants may be denied access to this program.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-4 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register for Twilight Fitness Hike in Limestone Canyon.

For families and children ages 12 and up who would like to join IRC-certified volunteers in OC Parks’ Irvine Ranch Open Space on a longer, slow-paced, family-oriented ride through sycamores, oaks, and habitat native to California. The route takes us to The Sinks, Orange County’s own “Grand Canyon.” Along the way, we will stop and talk about the local habitat, and hope to see some of our local native animals and raptors. The ride is an 8-9 miles with 400-800 feet of elevation gain that may require hike-a‐bike for some riders. Motorized recreation vehicles of any class or type are not permitted for recreational use.

The trail is a wide dirt fire road with natural hazards like sand, tree roots, ruts, rocks, dry creek crossings, and small hills. We will ride at the slowest rider’s pace, with numerous stops for resting, regrouping and/or interpretation.

Some trail side bike repair knowledge is appreciated. Allow 2-2.5 hours of riding time. To be able to ride with the group six months of trail experience is required. Riders need to have ridden in areas such as Peter’s Canyon, Chino Hills Telegraph Canyon, El Moro Canyon, and Aliso Woods. Riders must be able to ride/walk 10 miles on gradual uphill and downhill terrain. Riders must have their own mountain bike, helmet, 100 oz of water, and snacks. Parents, your child must be able to ride their own bike. Children’s bikes must have front shocks and 20 inch or larger knobby wheels. Please consider that this ride may be difficult for your child. Bring spare tubes for your child’s bikes as well as enough water and snacks for your family. Appropriate mountain bikes have knobby tires, multiple low gears and a front shock. Please do not bring road bikes, beach cruisers, BMX bikes, electric or motorized bikes, or attachments to your bike.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-3 activity on the land.  Please visit our FAQ page for answers to activity specific questions you may have prior to registering. To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page.

Learn more and register for Evening Family Beginner Mountain Bike Ride: Limestone Canyon to The Sinks.

Join us in the back-country wilderness for a journey filled with beautiful sights that are photographic and artistic sketching opportunities. Our journey begins in the afternoon. We will be deep in a secluded canyon, where time is measured in centuries, even millennia, in the sandstone cliffs of this ancient place called Limestone Canyon. You will board a 4-wheel drive vehicle for a 13-mile tour of the canyon and hills surrounding it. We will stop frequently for 15-30 minutes to admire the views, take photos, sketch landscapes, and answer questions.

Stops will include short walks with views of The Sinks, a trip up Cactus and Markel Spur, with optional, single track, one-mile hike into Box Springs or a 1.5 mile Markel Spur to East Sinks loop hike. Both the Box Springs and Markel Spur hikes provide the visitor a true back-country experience. An alternative, but similar, hiking trail may be used.

From the Augustine Staging Area, we proceed up an old ranch road that was paved to provide access to Irvine Lake and the mines in Black Star Canyon. At the research center, we head off-road up a narrow, windy, and sometimes bumpy trail to Loma Ridge and beyond. Bring your camera equipment, sketchbook, or just enjoy the ride.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-2 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering. To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page.

Learn more and register for Photo Journey Limestone Canyon: The Sinks, Loma Ridge Backcountry and Sunset.

Join us Sunday morning in OC Parks’ Irvine Ranch Open Space for a fitness-focused hike on the Hicks Haul Road, West Loma and Shoestring trails in Limestone Canyon. Hikers will enjoy wonderful views and a panoramic overview of Orange County. The hike starts at Hicks Haul Road staging area and will cover a distance of 8.25 miles, about 5 miles of the hike is on paved surface and rest on trails. Participants are expected to hike close to 3.5 miles per hour and come prepared with closed toe hiking boots or shoes, water, trail snacks, sunscreen, hat, day pack or fanny pack, and any other necessary equipment or supplies you might need to keep you safe on this hike.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-4 activity on the land. To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page.

Learn more and register for Sunday Fitness Hike at Hicks Haul.

Join us in beautiful Weir Canyon for this moderate paced cardio hike. Along the trail, you’ll pass through coastal sage scrub, grasslands, and oak woodlands where deer and bobcats are frequently observed. Multiple steep climbs and descents, and sweeping views, are included throughout this 6-mile hike.

Please make sure you are in excellent physical condition! Even though this is a slower cardio hike, it is faster than a walk. You must be able to hike 3+ miles per hour the entire time without stopping.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.  If you’re unable to participate, please cancel your registration promptly so others may register.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-4 activity on the land. Please review our Trail Tips and FAQ pages to ensure you arrive prepared for this hike.

Learn more and register for Moderate Cardio Hike: Weir Canyon Rifle Range Loop.

As the day starts to settle into the night in OC Parks’ Irvine Ranch Open Space, bats awaken, stir and streak into the evening sky. Come hear fascinating tales of our flying mammal. We will head out towards a popular roosting location as we watch our nighttime heroes begin their nightly adventures. This program is ideal to visually observe the bats in flight, though bat detectors are available to listen for their high-frequency calls. Be prepared to walk about 1/2 a mile. Dress warmly as it may be a chilly evening. A camping chair is welcome as we will have a short introductory presentation in the staging area before the walk.

Please note that you will be asked to adhere to the following measures during the activity in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level 1 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register for Bats: Heroes of the Night.