The White Synagogue is Sejny's most powerful stop. Built in the 19th century and gutted during the Second World War, it now serves as a cultural centre connected with the Borderland Foundation, with concerts, exhibitions, and work around the town's mixed Polish, Lithuanian, and Jewish past.
The building is plain inside, which makes the absence feel stronger. It is worth seeing not only as architecture, but as the place where Sejny has tried to talk honestly about the communities that once shared the town.