There are many numbered (and unnumbered) trails in the City of
Belmont Open Space, so I decided to use these numbers to create my
very first Mystery Cache. To find the coordinates of the actual
cache, you have to solve the easy math below. The trail map can be
found at the most trailheads in the open space (or on the
internet).
You will determine 4 numbers A to D from the trail map.
A = Trail # of the loop trail.
B = Trail # of the longest trail.
Now, list all the trails that are connected to trail # 11.
C = How many trails did you list?
D = Multiply all the trail #s in the list.
XX = A * B
YY = C * D
The cache is at N 37 30.0XX, W 122 18.0YY.
Congratulations to kablooey for the FTF!

You can validate your puzzle solution
with certitude.