There are many castles left on the territory of Ukraine, most of which have already been well-studied. One of the most mysterious is the medieval Tustan Fortress. It used to be a defensive castle and a customs office. Historian Oleksandr Alfiorov tells what is known about the mysterious fortress. What Tustan ghost castle looks like “There is a ghost castle in Ukraine-that is, it exists and does not exist at the same time. In the Stryi district of Lviv region, there are seemingly ordinary rocks. But when local researchers began to study the special grooves for beams there, they suspected that s…