Neuwerk is an island in the North Sea off the coast of Germany.
While Neuwerk is administratively part of Hamburg, this is of little importance to most visitors, as it is both closer to and more easily reachable from Lower Saxony.
A high dike surrounds the settled parts and is the highest point on the island (apart from buildings, that is)
There is regular ferry service to/from Cuxhaven (~1½ hours one way). Booking in advance is very advisable. Neuwerk also has a small harbor that can accommodate small boats, but you should be familiar with National Park regulations as some parts of the Wadden Sea are off limits even to boats.
As this island is close to the mainland and the seafloor is exposed during every low tide you can walk there to or from the mainland (~3 hours one way). This is only possible in guided hikes, due to safety and environmental concerns. There are no steep climbs (go figure), but the mud can slow you down and it can get quite windy. Outside of a few summer months fog is a major concern.
There are horse drawn carriages, called Wattwagen in German, that regularly make the trip to and from the island. This is the most scenic and probably also the most comfortable way of reaching the island. As cars are not allowed on the island and environmental protection laws are strict, Wattwagen are probably here to stay, even though they might remind you of a bygone "simpler" era.
As the island is small and (as common on German North Sea islands) has no cars, getting around is mostly done on foot. Unless you are mobility impaired this should be no problem as the island is small and relatively flat.
Cash is the name of the game. Even some hotels don't accept credit or debit cards.
Water is usually potable and brought from the mainland (originally via tanker now through a pipeline)
There is a special tourism tax that is levied on top of the going rate per person per night. The tax is €1 for every €50 the room costs. Below €10, no tax is levied and below €25 the tax is €0.50.
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