The Land Reutilization Authority in St. Louis holds about 12,000 unwanted properties:
https://www.stltoday.com/news/local/metro/lra-owns-the-st-lo...
The LRA usually ends up with these properties when they fail to receive any bids at the regular tax auctions. Fewer are falling into their hands, recently, because the hot housing market is driving folks to look at things they previously wouldn't have, but properties still routinely go unwanted:
https://www.stltoday.com/news/local/govt-and-politics/fewer-...
St. Louis is the market I'm most familiar with, but similar land banks exist in cities all across the country.
