The infamous block house. It shares several textures used in the flood control building. Possibly created by Rolf Mohr, as it was shared on his website.

The block house model can be found in the Plains MAX file, found in the Mystery Models 2 pack. A lot of the textures of this model is however lost.

Source: https://web.archive.org/web/19991022053743/http://www.geocities.com/EnchantedForest/9057/Trespasser.html