Kalmar is one of the oldest cities in Sweden and contains Sweden's best-preserved Renaissance castle. Although nowadays it is a thriving commercial center, Kalmar still retains many 17th-century buildings and sea captains' houses. The 13th-century Kalmar Castle has served as fortress, distillery, granary, and prison and now houses the county museum. As a matter of fact, traces of the past are found in architecture and cultural artifacts. Kalmar Castle, the Old Town and Kvarnholmen are the main attractions. The town has a vibrant night-life with musical events, theatre, pubs, dancing and in the summer, outdoor venues and sidewalk cafés where you can relax after the day's activities.