Sombrero Island

Sombrero is the northernmost islet in the Lesser Antilles. It is a 95 acre rock, one mile long and a quarter mile wide, 38 miles from Anguilla and separated from the mainland by the Dog and Prickly Pear Passage. The relatively flat top of the rock is 40 feet above the surface of the water yet the treacherous northern rollers are known to wash over the entire island even on relatively calm days.
Sombrero is best known for its Lighthouse. The flashing beam, 166 feet above sea level, protects ships passing from the Atlantic Ocean to the Caribbean Sea through the Anegada Passage. Sombrero Island is a dependency of Anguilla.

Sombrero, also known as Hat Island, is the northernmost island of the Lesser Antilles in position 18° 60’N, 63° 40’W. It lies 55 km or 34 miles north west of Anguilla across the Dog and Prickly Pear Passage. The distance to Dog Island, the closest island of Anguilla, is 39 km or 24 miles. Sombrero is 1.5 km or 0.9 miles long north-south, and 0.4 km or 0.25 miles wide.
The land area is 0.38 km2 or 95 acres.

Originally, when viewed from the sea, the island had the shape of a sombrero hat but mining operations have left the island with precipitous sides and a relatively flat top which is 12 m or 40 feet above sea level. The surface of the island is rough, and vegetation is sparse.
This mining operation yielded some 3000 tons of phosphate a year by 1870. By 1890, the phosphate reserves had been exhausted.


History of Sombrero Island

As a result of the Treaty of Utrecht in 1714, Sombrero passed into the hands of the British. In 1814, and again in 1825, a British geologist surveyed the island and found that it abounded in phosphate of lime (guano) and this was reported to the British Government.
In 1856 the Americans claimed the island, and in a very short period of time quarried 100,000 tons of phosphate to resuscitate the exhausted lands of the Southern States, the British then intervened and demanded compensation. The United States claim to the island was settled in Britain’s favour in 1867.

Sombrero, lying in the route of shipping from England to South and Central America, lay in an area with many hazards and in 1848 the Admiralty was asked to install a light on it.
On June 30, 1859 the Royal Mail Steam Packet Company’s ship Paramatta was wrecked on her maiden voyage on Horseshoe Reef which resulted in another request to the Admiralty.
The lighthouse was then built and first exhibited its light on the evening of 1 January 1868.

From the early 1870s until 1885 a Cornish mining engineer, Thomas Corfield, was Superintendent of Sombrero.
His duties at Sombrero were to organise means of conveying the guano to a spot which was convenient for loading the lighters to take the guano to the ships lying off the Island, see to the making of derricks and engine houses, arrange for the laying of the tram lines for the wagons, which were loaded at the quarries.
The guano was just piled in dumps near the engine houses and derricks. There was no semblance of a port and no beach. There was also the provision of labour. The black workers were picked up from various islands and lived in wooden huts during their term of service.

Stores and various supplies were obtained from a merchant at Philipsburg, St. Martins, a Mr Nesbit. Supplies were taken to the island in the Company’s schooner, the Logos.
This little ship was also used to take the black labourers to and from their homes up and down the other islands.
The superintendent’s house was a wooden bungalow near the middle of the island and round it were grouped the quarters of the technicians, store keepers, light house keepers and other wooden buildings.
On the side opposite to the main buildings was a small building used as his drawing office etc. There was a wide veranda round the house and he used to live there with his family, except near the hurricane season.

In 1890 the phosphate works on the island were abandoned and by 1893, the lighthouse had come under the authority of the British Board of Trade, later the Department of Transport. Administration of the light was carried out by Trinity House.
In 1931 the old light system was changed and improved to 200,000 candle power and the tower received its first major repair as the basement was encased in concrete.

On 20 July 1962, after the destruction caused by Hurricane Donna in 1960, the present lighthouse was put into operating and the old tower demolished on 28 July 1962. The lighthouse is located near the centre of the island, and reaches a height of almost 51 meters or 166 feet above sea level. It protects ships passing from the Atlantic Ocean to the Caribbean Sea through the Anegada Passage. Full responsibility for the light passed from Trinity House to the Anguillan Government on 1 December 2001.



The island is noted for the endemic Sombrero Ameiva, a widespread and easily seen lizard species on the island. A recently discovered dwarf gecko, Sphaerodactylus, may be endemic and has been tentatively named the Sombrero Dwarf Gecko. The Anguilla Bank Anole also inhabits the island.

The surrounding waters are feeding areas for hawksbill turtles. During the late Pleistocene, the island was inhabited by a now-extinct giant tortoise, Chelonoidis sombrerensis.

Sombrero has been identified as an Important Bird Area by BirdLife International because of its breeding seabirds. It supports internationally important numbers of:

  • Masked Boobies Sula dactylatra: 27 pairs (54 + birds, 4% of Caribbean population) 2002
  • Brown Boobies Sula leucogaster: 386 pairs (772 + birds, 5% of Caribbean population) 1999
  • Bridled Terns Sterna anaethetus: 270 pairs (540 birds, 4% of Caribbean population) 1998
  • Brown Noddies Anous stolidus: 700 pairs (1400 birds, 5% of Caribbean population) 1998
  • Sooty Terns Onychoprion fuscata