Visby is the largest city on the island of Gotland, and was once one of the most powerful cities in Europe. The entire island is full of ruins, artifacts and memories from its periods of greatness during the Viking period and Middle Ages when Visby was a member of the Hanseatic League. The town is surrounded by the Visby Ringwall, a huge 13th century stone wall that encloses the city. Inside the wall, Visby beckons with its medley of modern and medieval times.