It's inflated at the present time in one of those blown up fortresses? (6,6)
I believe the answer is:
bouncy castle
But I can't explain it at all! Could you help me understand?
(Other definitions for bouncy castle that I've seen before include "Inflatable structure for children's parties" , "[ENTERTAINMENT] loved by children" , "Blown-up, jumped-upon entertainment" , "Inflatable fort for children's play" , "Blown-up fortress?" .)