Sylt is one of the North Frisian Islands.
Bus is the easiest although bikes are also popular. On the bus a family ticket for 3 days all over the island is about 40 Euros.
Almost every restaurant on the island is seafood, with the fish burger being considered something of a takeaway speciality. The island is definitely not cheap with the prices somewhat inflated by the wealthy German tourists who seem to make up 95% of the tourist traffic.