Arterials dominate suburban life but this run satisfyingly avoids them all by passing under three bridges.
Technically this is a lollipop run rather than a loop run as the Marvin Gerst to Shaw Valley Connector
connects the parking lot to the loop. The first "bridge" looks more like a tunnel constructed of cement and corrugated aluminum, crossing under Carmel Creek Rd to the Shaw Valley Trail
that runs along the edge of the Grand Del Mar golf course.
A ways beyond the golf course, cross under the tall Carmel Mountain Rd bridge to ascend to the lip of Los Peñasquitos Canyon before descending the Side Hill
Trail into the canyon for a brief journey along a more intimate section of the Penasquitos Creek Loop
The exit is via the Carmel Mountain Connector
, the hardest part of the run, though continuing just a bit further west at the bottom of the Los Peñasquitos Canyon allows a less steep exit. After completing the ascent, a short trek north reaches the third bridge, a second passage under Carmel Mountain Rd. The Carmel Mountain Rd to Little Shaw Valley
trail completes the loop.