This tiny one-lane Timberland Avenue bridge over Saw Mill Run closed in about 2014, isolating two houses that had probably already been abandoned. The green one further back dates from the 1880s, the other one from the 1890s. There was once a group of about half a dozen houses here; these are the last remnants, and they will be either torn down or eaten by jungle eventually. It will become another vanished village along Saw Mill Run, like Seldom Seen, and almost no one will remember that there was a tiny country hamlet here in what is now the middle of the city near the south end of the Liberty Tubes.

This little bridge isn’t much to look at, but it certainly dates from before 1909.

What caused the houses to be abandoned? Probably the same thing that caused them to be built in the first place: their proximity to Saw Mill Run. In southwestern Pennsylvania, minor rivers like this one are subject to flash floods once in a while that might have reached some of the houses here, and certainly would have isolated them if the bridge was under water. Perhaps a worse problem was that, as the South Hills developed farther upstream, Saw Mill Run became something like an open sewer, known for its pollution and noxious stench. Both floods and pollution made houses along the run undesirable. There is much less pollution now, but it is not likely that this property will become valuable enough to make it worthwhile rebuilding the bridge.

On planning maps, these houses are in Bon Air, but right on the border with Brookline. The Brookline Connection site has some information about Timberland Avenue. The first picture in that article shows these two houses as they appeared in 1909, and the second shows this bridge.