Just a strange expression:
You trash a Fortress
and...
• put it in hand Fortress.
• may reveal Market Square.
Joining game #603077 on tokyo.
It's because you can choose the order to resolve the "when you trash" effects. In this case, the order doesn't matter, but in other cases it could matter
I guess the point here is that "put it in hand Fortress." is a strange expression, and "put the fortress in your hand." or something would be better ;)