Observatory Mesa Natural Area

Observatory Mesa Trail Plan

Everyone is invited to come learn about the updated draft trail plan, including plans for formalizing some hiking and mountain bike trails and connections, adding signage, re-naturalizing some social trails, and adding designated adaptive cycling trails. To see a recording of the June 14th public meeting, and to review the plan, please visit https://www.flagstaff.az.gov/4870/Greater-Observatory-Mesa-Trail-Plan; the public comment period ended July 16, 2023, but you will have one more opportunity in coming months. Thank you!


The City of Flagstaff acquired Observatory Mesa Natural Area in December 2013 with funding from the 2004 voter-approved Open Space bond and a 2013 Arizona State Parks Growing Smarter grant. We welcome you to experience the expansive views and diverse plants and animals found in this 2,251 acre native forest ecosystem. Observatory Mesa serves as an important wildlife corridor for large mammals traveling between the San Francisco Peaks and the Mogollon Rim.

Motorized Access

Observatory Mesa is a non-motorized area. There are currently two parking areas that allow access to the Mesa, one at Thorpe Park and one along Forest Service Road 515.

Thorpe Park Bark Park

From downtown Flagstaff, travel north on North Humphreys Street and turn left on West Cherry Avenue. When you reach the end of Cherry Avenue, turn right onto North Thorpe Park Road. The parking area will be on the right near the ball fields. From the parking area, you can access Observatory Mesa by taking the F.U.T.S. trail on the west side of North Thorpe Park Road near the disc golf course.

Forest Service Road 515

From downtown Flagstaff, travel south on South Milton Road. Turn right on Route 66 and travel approximately 4 miles to merge with I-40 West. Take the next exit for A1 Mountain Road. Turn right onto A1 Mountain road, which turns into Forest Road 506. Continue straight onto Forest Road 515 and pass through the Forest Service gate. Please park when you reach the Observatory Mesa kiosk.

Observatory Mesa Natural Area Flagstaff, Arizona
Photo Credit: Tom Bean
Map of Observatory Park


Observatory Mesa is a great place to hike, mountain bike, photograph the natural environment, watch wildlife, and experience fall colors. Horseback riding is permitted throughout Observatory Mesa, but are prohibited on the Tunnel Springs Trail. Please do not ride your horse during wet conditions to protect the trails.

Observatory Mesa is open to the public year road. There are no facilities available.

Trail Information

Trail NameDistanceImportant Information
Observatory Mesa Trail1.6 milesRelatively flat, single track trail. Connects with Tunnel Springs and Mars Hill Trails at Forest Road 515.
Tunnel Springs Trail1.9 milesProvides access from Railroad Springs community to Observatory Mesa. A tunnel provides
a safe railroad crossing. Steady ascent to the top of the Mesa.
Mars Hill Trail1.9 milesTrailhead located at the Thorpe Park Bark Park. Short, steep climb to ascend the Mesa.

Note that there is a draft Observatory Mesa Trail Plan, where it is proposed to formalize some hiking and mountain bike trails and connections, add signage, re-naturalize some social trails, and add designated adaptive cycling trails. Your comments are invited! Click on the link at the top of this page for more information.


Observatory Mesa is a day-use only area. Camping, campfires, and woodcutting are strictly prohibited.

Motorized travel is limited to Forest Service roads that are designated as "open" on the most recent Motor Vehicle Use Map. You can download a geo-referenced version of the map to your smartphone.


Observatory Mesa Natural Area is within Game Management Unit 11M, as designated by the Arizona Game and Fish Department (AZGFD). Discharge of firearms for any purpose is prohibited within the Natural Area. Archery hunting of big game is permitted per AZGFD hunting regulations. However, archery hunting is not permitted within a quarter mile of a trailhead, picnic area, or occupied building. Motorized retrieval of game is also prohibited.

Upcoming Events

Observatory Mesa Invasive Plant project is out for bid until September 11, 2023 12pm. We received a grant from AZ Department of Forestry & Fire Management to manage invasive weeds on Observatory Mesa Natural Area. Please visit the bid details for more information.

Open Space Working Group meeting Wednesday 9/13/23 10am at Frances Short Pond. Come learn more about Flagstaff's Open Space properties and current projects.

To learn about more upcoming events, follow us on Facebook https://www.facebook.com/flagstaffPROSE or Instagram https://www.instagram.com/flagstaffprose/.

To set up a volunteer event for your group, email Robert Wallace or call at 928-213-2327.