The island is made up of a sandy core of geestland and features an extended beach all along its west coast, facing the open North Sea.

Sand dunes are a characteristic part of Amrum's landscape, resulting in a vegetation that is largely made up of heath and shrubs.

Amrum is a refuge for many species of birds and a number of marine mammals including the grey seal and harbour porpoise.

With the island hosting many endangered species of plants and animals, its soil being largely unproductive for agriculture and as a popular seaside resort in general, Amrum's population today almost exclusively lives from the tourism industry.

Amrum's area measures 20.4 km2,[2] making it the tenth-largest island of Germany (excluding Usedom which is partly Polish territory).

[4] Amrum's surface area has however been subject to constant change due to land loss and gain caused by the sea.

On the geestland core, one can find extended areas of heath and woodland which form a strip that runs along a north-south line on the axis.

West of this woodland strip, a region of 838 hectares (2,070 acres) is covered with dunes[1] that run all along the island for about 12 km.

Notable sights there include the church of St. Clement with its "talking gravestones", the Öömrang Hüs - a museum of local history, a wind mill and the Cemetery of the Homeless.

Steenodde, also a neighbourhood of Nebel, had long been Amrum's only port until Wittdün, founded 1890, had taken over as the island's major ferry terminal.

It is unknown whether the Ambrones, who together with the Cimbri and Teutones threatened Rome around 100 BC, stemmed from this island which back then was still connected to the mainland by a land bridge.

The oldest known record of Amrum island has been found in the Danish Census Book of King Valdemar II of Denmark from 1231.

[10] Next to salt making, agriculture, fishery and whaling, merchant shipping was one of the main sources of income for a long time.

Hark Olufs, a sailor from Süddorf who had been enslaved by Algerians in 1724, advanced to the rank of a General until he was allowed to return to his native island in 1736.

During the Middle Ages, Amrum, as well as all of North Frisia proper, belonged to the so-called Uthlande, the Outer Lands, which only successively became parts of the Danish realm or the Duchy of Schleswig.

In 1920, the Schleswig Plebiscites resulted in a clear majority vote for Amrum staying with Germany, while Tondern fell back to Denmark.

[11] Among other factors, the decrease owed to the fact that large parts of Amrum's population had emigrated — mainly to the United States.

Eventually, tourism began only to flourish on the island when a seaside resort was established in Wittdün in 1890, which also led to a rapid increase in population.

[12] On 29 October 1998, the cargo ship Pallas ran aground off Amrum, causing a severe oil spill in the region.

Due to the isolated location of the islands, the North Frisian dialects developed so differently, that Öömrang can be understood by people from Föhr, yet is hardly recognisable for those from Sylt or mainland Nordfriesland.

Amrum's national costume for girls and women is coloured black and white and is amply decorated with silver ornaments.

During the summer season, a fast passenger boat offers services between the ports of Hörnum on Sylt, the Hallig Hooge and the harbour of Strucklahnungshörn on Nordstrand.

Plants and wild animals on Amrum are marked by the proximity to the sea, but some also distinguish themselves by extreme rarity and a high ecological value worth of protection.

This fact was acknowledged by the establishment of two nature reserves and Amrum's proximity to the Schleswig-Holstein Wadden Sea National Park.

Its grassland grows plants such as Harebell (Campanula rotundifolia), Sea Thrift (Armeria maritima) and Carthusian Pink (Dianthus carthusianorum) and several species of hawkweed.

Occasionally in December and January, young grey seals are washed ashore on Amrum's beaches due to storm surges and are thereafter nursed by the adults.

A 1940 report mentioned several worms like Nematodes, Archiannelida, Oligochaeta and Turbellaria, crustaceans like ostracods, and ciliate protozoans in the sands of the Kniepsand beach.

[26] Since the 1980s, the abundance of harbour porpoises in the sea off Amrum and Sylt has been increasing and a protected marine area was created in 1999 to provide shelter for them.