The Bay Area features several unusual and distinctive microwave sites, far different from the modular construction normally used by AT&T. Part of this is becaus

The Bay Area features several unusual and distinctive microwave sites, far different from the modular construction normally used by AT&T. Part of this is because some of these sites were relatively early ones, part is because of local zoning requirements, and part is because some of them were originally built by GTE. Perhaps the most interesting is the Oak Hill site, which I believe is nearly unique, with just one other of a similar design. The Redwood City site is interesting in its own way, as I believe the building below contained the Redwood City tandem at the time prior to its elimination in favor of a single, very large 4ESS tandem at Oakland. It was not very typical for tandem switches to be colocated with large microwave sites, usually being end offices on the microwave network with only two antennas (tandem offices are typically in large cities so AT&T often used a "city and junction" pattern where the tandem office, named for the city, was an end office on a short leg from a large microwave site on the outskirts of town named city junction). The exceptions tended to be in highly urbanized areas where space was difficult to obtain, or a few odd cases like Mojave where an end office grew over time into a gateway site.