Putting the map away, Varin casually leaves the inn. And by casually, I mean with the usual warranted wariness of his surroundings, especially the people. Once out of the establishment, he pulls his cloak closer and does not directly go to the starting point, rather adding a few small detours, checking whether they are being followed. It would not be the first time, and it has happened for lesser things. Once it seems as safe as it can be in a place like Wilverton (and without people nearby), Varin tells the group in a quiet voice:

"I found the map in an abandoned part of Castle Wilverton. The tyrant and his minions don't care much for reading and the like, so I sometimes go there. Peace and quiet in the ruins. Found the map in a book on hill giants. Seemed like a rare opportunity. I hope the book's subject isn't also a hint of the dangers we might come across."

Nothing else to do but to start following the map, should his dear companions still be willing.