|Ortsteil of Sylt|
|Area||37.97 km2 (14.66 sq mi)|
|Elevation||1 m (3 ft)|
|Population||5,833 (31 December 2007)|
|- Density||154 /km2 (398 /sq mi)|
|Time zone||CET/CEST (UTC+1/+2)|
Sylt-Ost is a village, former municipality and seaside resort on the island of Sylt, in the district of Nordfriesland, in Schleswig-Holstein, Germany. The place is the seat of the Amt Landschaft Sylt. A public referendum in May 2008 decided for the merger of Sylt-Ost with the town of Westerland in 2009. Since 1 January 2009, it is part of the municipality Sylt.
The municipality is divided into the five formerly independent villages of Archsum, Keitum, Morsum, Munkmarsch and Tinnum. The current municipality was created in 1970.
A prehistoric settlement in this area is proven by archaeological research. According to old lore, all inhabitants of Archsum fell victim to the plague in 1350. Afterwards the village is said to be re-settled by people from Rantum. In 1634 the sea dikes were destroyed by the Burchardi flood. Only in 1938, due to the construction of the neighbouring Rantum Basin seaplane port, Archsum was again completely protected by dikes.
Due to its numerous alleys and the high content of old trees, Keitum is today regarded as the island's "green village". Already in the late 12th century the church of St. Severinus was built there.
Morsum is located in a heath on a 1.8 kilometres long cliff shore, which reaches up to 21 m of height.
The late Romanesque church of St. Martin was built in the 13th century from granite blocks and cobblestones. Instead of a proper tower, it features a small separate wooden bell tower. In the 15th and 16th century, this village was also frequently struck by the plague. Since 1958, Morsum is recognised as a climatic health resort.
The village is first recorded in 1422. In 1859, a port was constructed which featured a ferry link to the mainland harbour of Hoyer.
Tinnum is the municipality's biggest settlement and forms a structural unit with Westerland to the west. Not least because of the central location on Sylt, a number of business parks can be found here, which are of import for all tourism-related enterprises on Sylt. Moreover, several great discount shops are situated here, thus Tinnum, in addition to Westerland, plays a central role in provisioning local citizens and guests.
The original village of Tinnum, which used to be the seat of the island's bailiff from 1547 to 1868 and hosted the local prison and courthouse, was first mentioned in 1440. The bailiff's house of 1649 is one of the oldest remaining buildings on Sylt.
Near Tinnum there is also the so-called Tinnumburg, an eight metres tall ring wall with a diameter of 120 m which was built around the time of Christ's birth.
- 1986-1996: Heinz Maurus, CDU
- 1996-2005: Ingbert Liebing, CDU
- 2005-2008: Christoph Schmatloch, CDU
- 2008: Erik Kennel
The coat of arms was designed by a Sylt artist and granted in 2002. The five mullets (stars) in it symbolise the villages of the municipality. The herring is meant to depict the former importance of fishery for the area, it was already used as the seal of the Sylt bailiffs in the 17th century. The colours are the traditional North Frisian colours which are also reflected in the island's national costume.
The most important factor of income is tourism, which nowadays influences almost any business on Sylt. While being most important prior to the arrival of the tourist business, agriculture meanwhile plays a minor role.
Notable people 
- Gustav Jenner (1865–1920), born in Keitum, was a composer and conductor.
- Boy Lornsen (1922–1995), born in Keitum, was a sculptor and author of children's literature.
- This article incorporates information from