Not on top, not on the bottom, not inside, be nice to your bridge troll and maybe he will show you the letter on the side.
As of August 2022, Langston Blvd is a shiny new road connecting Eagle Drive and Hwy 99. This road may not be visible from the geocaching map and possibly not from Apple or Google yet either, but it's what you'll use to access this cache. Under the tastefully designed bridge is a paved walking trail along the ponds that dot the area. Much of the area is still being developed, but the cache is safely accessible and comes with a nice viewof the surrounding ecosystem.