The easiest approach to the hide is along the Cordilleras Trail, a smooth level footpath that parallels a road maintained by the San Francisco water authority.
Along the way, you'll also observe a pleasant, level grassy meadow nestled in the valley, a rarity in this neighborhood of steep, deadend canyons and gulches. It's a fake. The terrain is totally manmade, and conceals the twin giant tubes of the Hetch-Hetchy aqueduct buried beneath the grassland. Near the hide, the pipes make a hard left turn and bore through the ridge that carries I-280, in what's called the Pulgas Tunnel, ultimately emptying into the Crystal Springs Reservoir.
But what happened to the stream that originally carved out this valley? That's what this cache will show you. The waters of upper Cordilleras Creek vanish here, into a large grate, and are carried in their own giant tube under the meadow, to emerge outside the park. (By a pump station across Edmonds Road from the Pulgas parking area.) One of those little marvels of engineering you can walk right past!
You are looking for a small, camo'ed micro cache. Bring your own pen or pencil. This spot can be fairly busy for a hiking park (hence the camo), due to the dog run area at the top, so you may want to have a cover activity prepared - some slow stretching will do. You do not need to cross any fences or other barriers to reach the cache. You also do not need to move any man-made objects or downed wood. Good luck!
As of 9/26/07 the original hide was replaced with a new, still camo'ed micro cache. I'll accept second logs from those who found the first, as this new hide is quite different. You should not have to remove the container from its attachment to obtain the log, though you may want to bring a small pokey log extractor along with your pen or pencil.