The activities below are offered by a variety of organizations and their dedicated volunteers. All programs are FREE unless noted below. Programs led by IRC-Certified Volunteers require pre-registration, which closes at 4 p.m. on the day prior to the event. No walk-up registrations will be permitted for these events. For policies of other organizations, please use the sign-up information provided. For mobility device policies click here.
Note: Minors must be accompanied by a parent or guardian for these events. For programs requiring online registration, each adult and child must be registered. |
Need help? For the fastest answers, look for organization-specific contact information in each event listing (click More Information for full listing). If no contact information is listed, email info@irconservancy.org for assistance.
Updated Difficulty Ratings: The Hiking and Fitness Difficulty Ratings have been updated to reflect our current activities. Please click below to read the ratings.
Click here to learn more about IRC-Certified Volunteers. • Click here to learn more about the Difficulty Ratings.
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Saturday, June 14, 2025
Limestone Canyon – Weekend Hike to Both Sides of the Sinks

Join us on this moderate-paced hike over the ridge and the through beautiful Limestone Canyon Nature Preserve, part of OC Parks’ Irvine Ranch Open Space. We will enjoy short breaks at the East and West Sinks viewing platforms before hiking back through the canyon. We will enjoy a view of wonderful vistas in addition to spectacular view of The Sinks. This hike involves hiking on both double and single-track trails with an elevation gain of 1000.
Family Hike: Agua Chinon

Enjoy an afternoon family hike in Agua Chinon, part of OC Parks’ Irvine Ranch Open Space. We hike a gradual climb of 500 ft elevation as we watch for red-tailed hawks and mule deer. This activity originates in the City of Irvine and travels into Limestone Canyon Nature Preserve. The hike will average 3 miles round trip at an easy pace with a medium level of interpretation. This program is for participants who would enjoy a slower-paced gradual climb hike. Hikers should be in good health able to do a beginning hike over a variety of terrains. Wear comfortable clothes and sturdy shoes and bring water for the hike. Be ready to enjoy the sounds and smells of early evening.
Sunset Fitness Hike on Paved Hicks Haul Road: Both Sides of Loma Ridge

You will enjoy a gorgeous sunset with panoramic views of Orange County while hiking in OC Parks’ Irvine Ranch Open Space on the paved Hicks Haul Road. This hike travels 6 miles, out and back crossing over Loma Ridge. This is the perfect activity for you to get your work-out in and view the sunset. The hike is conducted at an average pace of 3 miles per hour, but you may travel a bit faster or slower, at a walk, run, or jog depending on your comfort level. 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.
Bats: Heroes of the Night

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.
Sunday, June 15, 2025
Sunday Fitness Hike at Hicks Haul

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 8.5 miles, about 5 miles of the hike is on paved surface and rest on trails. Participants are expected to hike close to 3 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.
Earthcache Hike to East Sinks

Come and hike with us to the East Sinks in Limestone Canyon, location of the Earthcache site — a special place people can visit to learn about unique aspects of the Earth — listed on www.geocaching.com. The cache is titled “The Sinks- Irvine Ranch Wildlands, GC1ZB6V.” This hike is open to existing geocachers, those curious about geocaching and non-geocachers alike. There will be as much time as needed spent at The Sinks so all geocachers can record their data and make their observations to confidently log their visit to this cache site.
Slow-paced Mountain Bike Ride: Limestone Canyon/East Sinks

Enjoy the relaxation of riding in the wilderness on empty trails. Join us on this docent-led mountain bike ride through Limestone Canyon, part of OCParks’ Irvine Ranch Open Space. We will visit the East Viewing Platform for a panoramic view of the geological feature call The Sinks. The route to The Sinks will include a fun downhill ride on the Dripping Springs single track. The return route will take us on the Limestone Ridge single track with views of Limestone Canyon, Santiago Canyon and the Santa Ana Mountains.
This is a slow-paced ride designed for the beginner that has experience riding fire roads such as Limestone Canyon or Telegraph Canyon but wants to develop their climbing and riding abilities. The ride can also be enjoyed by more advanced riders looking for a relaxed ride in a beautiful setting.
Tuesday, June 17, 2025
Tuesday Morning Fitness Hike on Paved Hicks Haul Road

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.
Evening Hike on Hicks Haul Road

Enjoy an evening hike through stunning rock formations and fragrant native plants as you listen to the sounds of nature. During this hike in the Irvine Ranch Open Space, you may travel at various hiking speeds based on your comfort level. This out-and-back program travels 3.5 miles round trip up to scenic Loma Ridge and back down. Please bring a red-tinted flashlight as the return portion of the hike may be after sunset.
Wednesday, June 18, 2025
After Work Fitness Hike on Paved Hicks Haul Road

Join us every Wednesday night in OC Parks’ Irvine Ranch Open Space for a fitness-focused hike on the paved Hicks Haul Road. 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 an average of 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.
Saturday, June 21, 2025
Bats: Heroes of the Night

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.
Sunday, June 22, 2025
Sunday Fitness Hike at Hicks Haul

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 8.5 miles, about 5 miles of the hike is on paved surface and rest on trails. Participants are expected to hike close to 3 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.
Evening Family Beginner Mountain Bike Ride: Limestone Canyon to The Sinks

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.
Monday, June 23, 2025
Bright Birds of Spring in Limestone Canyon – Bird Walk

Birds are among the most colorful and entertaining forms of wildlife on the Irvine Ranch Natural Landmarks. Bring your binoculars and join us on a slow/medium paced walk in OC Parks’ Limestone Canyon, as we search for resident and visiting birds of the local coastal sage scrub, oak woodland, riparian, and grassland habitats. We will discuss the diverse features of the birds we observe and how they match the season, their habitat and lifestyle. We will travel mostly on ranch roads, usually without shade. Beginners to advanced bird enthusiasts are welcome. Please wear sturdy shoes suitable for hiking and bring water, along with sun protection such as a hat and sunscreen. Bring a small birding field guide if you have one. A few binoculars will be available to borrow.
Tuesday, June 24, 2025
Tuesday Morning Fitness Hike on Paved Hicks Haul Road

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.
Butterfly Series: Limestone Canyon Butterfly Habitat Islands

Spend your morning helping to remove weeds and rebuild berms within the butterfly habitat islands in Limestone. With your help we will be able to maintain “islands” of host and nectar plants for butterflies in decline in Limestone Canyon. You will be transported from via a safari style truck from butterfly island to butterfly island through a beautiful oak woodland.
Evening Hike on Hicks Haul Road

Enjoy an evening hike through stunning rock formations and fragrant native plants as you listen to the sounds of nature. During this hike in the Irvine Ranch Open Space, you may travel at various hiking speeds based on your comfort level. This out-and-back program travels 3.5 miles round trip up to scenic Loma Ridge and back down. Please bring a red-tinted flashlight as the return portion of the hike may be after sunset.
Wednesday, June 25, 2025
After Work Cardio Hike in Limestone Canyon: Limestone Ridge

Come along with us on this afternoon fitness hike through beautiful Limestone Canyon Nature Preserve. You’ll be rewarded with a spectacular view of The Sinks as well as sweeping views of Orange County and the Santa Ana Mountains. This is a 10 mile fitness hike, completed in 3 hours and includes a 1000+ foot elevation change. The hike is for experienced, physically fit hikers who enjoy the challenge of multiple steep climbs and descents.
After Work Fitness Hike on Paved Hicks Haul Road

Join us every Wednesday night in OC Parks’ Irvine Ranch Open Space for a fitness-focused hike on the paved Hicks Haul Road. 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 an average of 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.
Thursday, June 26, 2025
Thursday Morning Trek: Limestone Canyon and Dripping Springs

This week in OC Parks’ Irvine Ranch Open Space, we’ll hike in Limestone Canyon to Dripping Springs. The hike is a 7-mile loop hike which includes some hills and descents. In addition to the springs, we will enjoy panoramic views of the wildlands from East Loma. Please bring water, a trail snack, sun screen, hat, and any other necessary equipment to keep you safe on the trail, and wear sturdy, closed-toe hiking boots. Participants must be able to hike 7 miles with an elevation gain of 1300 feet at an average moving rate of 3 miles per hour. Each hiker must carry his/her own water and supplies.