Make sense to me that they would be destroyed (discarded), since the fortress containing them was. But this came up in my first ever Type 2 game last night, when I played Land Dispute. What would happen to the cards inside fortresses like these? I looked for "discarding a fortress" in the REG and couldn't find it.
Storehouse
Kingdoms of the World
Goshen
The Darkness
Tabernacle/Temple
Raider's Camp
High Priest's Palace
and many more "card holding" fortresses I can't think of right now....
Thanks!