Oh lordy, if there's ever a great trail run that will make you feel like David Gest after Liza Minelli had a few cocktails, Waterdog Park in Belmont is it. It's a woodsy, canyon trail, with canopies of live oak, eucalyptus, and all other kinds of native California foliage. Apparently too, it was part of the original road to Half Moon Bay, and is over 130 years old.
Regardless, for the amateur to experienced trail runner -- and mountain biker as well, the various extensions of the trail provide all kinds of rolling and steep hills that will burn your glutes to the point of feeling like white hot coals. Here's a link to the various trails within Waterdog Park. I highly recommend starting out at Lake Rd. & Hallmark Drive, then follow the John Brooks Trail, the Elevator Trail to Carlmont Drive, then hit the streets on Carlmont Drive up to the trail head at Lake Rd./Lyall, then the Lake Road Trail back to where you started. To mix it up even more, you can then cross Hallmark, go up Upper Lake Road Trail where you can connect to either the Crystal Springs trail (where the cross country teams run), or venture down Sheep Trail to hook up with Canada.
But, like I said, leave your glutes at the bottom of the hill, cuz you won't be needing them as you make your way up some of the nastier hills!

