Maps - Course

This page has course Maps and turn-by-turn directions for the Lost Boys Ultra 50 mile / 55 kilometer courses!


The Lost Boys Ultra Trial Run - 50 mile / 55k is a point-to-point trail ultramarathon which starts on the Desert Floor of the Anza Borrego Desert State Park, 75 miles east of San Diego, heads west over the mountains and finishes in the Cuyamaca Rancho State Park. This beautiful and extremely challenging run features spectacular geography, historical trails, contrasting landscapes and incredible views. The first half courses through desert washes, canyons and mountain valleys including a brief section where runners must climb over some dry rock waterfalls. Ascending out of the desert, the mountainous second half climbs and descends through a lush alpine environment. 

The 50 mile course has approximately 28 miles of trails, 4 miles of desert washes without roads or trails, and 18 miles of jeep roads. With over 9000' of climb and 6100' of descent and an elevation range of 1200' to 6,512'. All but 4 miles of the course is contained within the state parks. 

Well equipped aid stations as follows:

NEW: 55 kilometer start line area (Blair Valley) explained:
  • The 55k race will start at the north west end of Blair Valley. Runners will run the short 1/2 mile dirt road around the edge of the the dry lake bed then will turn right and join the 50 mile runners as they cross the dry lake bed and will follow the 50 mile course for the remainder of the race!
  • When entering the Blair Valley aid station the 55k runners will stay in the shoot off to the RIGHT and will not receive aid and will not check-in with their bibs at this station. 
  • At the Blair Valley aid station the 50 mile runners will stay to the LEFT and are required to enter the aid station and check-in their bibs. 
  • Below is a map of the Blair Valley area showing the changes: