The newly completed Bay Trail spur goes from the parking area of the Fairfield Inn to the area beside the cache. There is legal parking for trail users clearly marked to the east of the Fairfield Inn at the P1 waypoint. From there it is a walk of less than 0.17 miles/245 m to the cache area. The cache location is just a bit south of the end of the paved portion of the Bay Trail. The trail here has seen major improvements over the last few years, the original terrain rating was a 3!.
You may reach the Fairfield Inn from Great America Parkway by going north past Route 237, turning right on America Center Court and following that road to its end. The P1 parking area will be on your right. If the four allotted spaces are filled you may park at the Alviso Education Center parking area (P2 waypoint), across Gold Street and on the other side of the railroad track. You will follow the dirt road along the river then cross the track at the crossing gate further south (see my note of 7/24/2019). Fairfield Inn route is more direct and safer as you do not cross the active rail line.
To reach the trail from the Alviso Educational Center parking area (P2 waypoint), cross Gold Street at the south trailhead of the river trail and continue west towards the tracks. This is a gravel paved road with a gate to block large vehicular traffic. Continue to the tracks and go south and parallel to them for a few hundred feet, to the railway crossing, and a gate to the hotel parking area. There are painted arrows in the direction of the trail. If the gate is locked, follow the fence north to where it opens to the paved trail
Update 3/6/2021: Cache is moved 260 ft/79 m SE to be outside the boundary of the Don Edwards NWR. If we can find a better spot we will move it again. The cache is now a micro small. The hint and description are adjusted. It is not necessary to trample any landscaping to reach this cache.
VTA bus route 59 serves the Alviso area. The fastest way if you are taking the bus is to get off at a stop along Gold (Lafayette) Street and follow the instructions for the P2 parking waypoint.
Congratulations to duckeylee for FTF