Back in medieval times, Visby’s lush urban park was actually the town’s Hanseatic harbor. When the harbor eventually filled in and became too shallow for most ships, the port was moved and Almedalen was eventually planted with elms, creating a pretty park for the town’s citizens. Today, the area is busiest during Almedalen Week, which takes place each summer. An important event in Swedish politics, it was started by Prime Minister Olof Palme and includes addresses by many of the country's political leaders from all parties. The rest of the year, you'll find people strolling through the landscaped grounds. During the summer months, you can also climb to the top of Kruttornet for views of the city’s rooftops. Visby’s oldest structure, the defensive tower dates back to the 1100s and was later incorporated into the city walls.