Oops! It turns out the old roundhouse in East St. Louis was demolished sometime in the last decade, and all that is left are the concrete foundations, and the rapidly filling pits where the locomotives once drove in to be serviced. The roundtable had already been filled in completely years ago.
It turns out this was known as the Cone Yards, part of the Baltimore and Ohio (B&O) Railroad, which you can see in its heyday in these remarkable photographs. You can see the roundhouse as it looked only 26 years ago, in January of 1995; it’s hard to believe the building deteriorated so quickly. Here is another picture looking out from the roundhouse at the turntable.
What is perhaps so shocking about the downward spiral and deterioration of this building was just how recently it was abandoned, according to the excellent link above. I had just thought it had been abandoned back in the 1960s at the latest, but it seems to have still been at least rudimentarily maintained into the 1990s. It was a complete disaster only a decade later.
One of the giant floodlight towers is still standing, but not much else.
Someone is clearing the huge volunteer forest to the north; I do not know why. I do know that there had been hopes for massive development after the completion of the new Mississippi River bridge, but it has been slow in coming.