This loop - Old Mission Dam to Oak Canyon Trail to Grasslands Loop Trail to Grasslands Crossing Trail to Father Junipero Serra Trail - may be thought of as a concentrated overview of Mission Trails Regional Park. In a relatively short 1.8 miles the loop passes historic landmarks, oaks along a dry riverbed, rolling hills, and a river crossing.
Start at the parking lot for the Old Mission Dam. A short trail leads directly to the dam, which is listed on the national register of historic landmarks. The dam was built 200 years ago: work started in 1809 and was completed in 1815. The fathers of the Spanish Mission San Diego de Alcalá directed the work using native Kumeyaay laborers. Boulders, adobe bricks, and tiles were cemented together with crushed seashells and limestone. Its construction is especially impressive considering that the work was done with hand tools and considering that an aqueduct was also constructed to carry the water from here to the mission that sat 6 miles away.
After examining the dam, follow the Oak Canyon Trail north. The first section of the trail is fairly level, but at the fork for Grasslands Loop Trail the trail gets much steeper. For the loop described in this adventure, take the fork to Grasslands Loop Trail. If you have a few extra minutes, consider exploring the canyon, which has been dry for the past few years due to drought.
Grasslands Loop Trail opens up into a vast area of rolling hills. Many birds rest in the shrubs and trees along the trail, so keep an eye out for them. Kwaay Paay Peak can also be seen from the trail. Grasslands Loop continues all the way back to the dam, but an alternate route follows Grasslands Crossing Trail (popular with mountain bikers) over Grasslands Crossing back to Father Junipero Serra Trail. It’s a quick walk along the paved trail, through chaparral, back to the parking area.
Leashed dogs are allowed on all the trails mentioned in this adventure.