With its own stock exchange, banking system and navy in place by the end of the 16th century, Hamburg has long been an important city. The efficient, straightforward and integrated HVV transit system offers a route planner in English. Having sprung up around a 9th-century castle, Hamburg has some unique sites, including landmark St. Michael's Church and museums showcasing art to erotica. For another look into this port city's wild heart, visit Reeperbahn, Hamburg's notorious nightlife center.