Mersea Island (centre right) viewed from the south
Mersea Island shown within Essex
|OS grid reference|
|Civil parish||East Mersea
|Sovereign state||United Kingdom|
|Postcode district||CO5 8|
|Ambulance||East of England|
|EU Parliament||East of England|
|UK Parliament||North Essex|
Mersea Island is the most easterly inhabited island in the United Kingdom, located marginally off the coast of Essex, England, 9 miles (14 km) to the south-east of Colchester. It is situated in the estuary area of the Blackwater and Colne rivers and has an area of around 7 square miles (18 km2). The name 'Mersea' is derived from the Old English meresig meaning 'island of the pool'.
Mersea Island is one of 43 (unbridged) tidal islands which can be accessed on foot or by road from the British mainland.
The island is joined to the mainland by a causeway known as The Strood. This carries the Mersea–Colchester road (B1025) which is often covered at high tides and especially during spring tides. It is close to the much smaller Ray Island. It is separated from the mainland by the Pyefleet Channel to the east and the Strood Channel to the west. There are two main settlements on the island; the small town of West Mersea and the village of East Mersea. This is also a small hamlet at Barrow Hill to the north of West Mersea.
There are also 6 Caravan/Camp sites on the island providing jobs and significantly contributing to the local economy predominantly during the summer months.
Many small shops and ice cream business serve the tourism on Mersea's beaches.
The island has its own newspapers, the Mersea Life and the Mersea Island Courier. It also has full broadband coverage and the majority of properties, excluding those too close to the beach, can receive Freeview signals.
There is evidence of pre-Roman settlement on Mersea in the form of "red hills" which are evidence of Celtic salt workings. A large Romano-British round barrow near the Strood contained the remains of a cremated adult in a glass urn, within a lead casket, now in the Castle Museum, Colchester. A large mosaic floor was found near West Mersea church.
The Anglo-Saxons built the church at West Mersea (St Peter & St Paul) which may have been founded as early as the 7th century. It was damaged by Norse raiders in 894 and rebuilt afterwards. A moat at East Mersea church (St Edmund, King & Martyr) is thought to be the remains of a Danish encampment. The Strood causeway was also built by the Saxons; oak piles discovered in 1978 have been dated by dendrochronology to between 684 and 702. By 950, there was a Benedictine Priory at West Mersea and land at West Mersea was granted to the Abbey of St Ouen in France by Edward the Confessor in 1046.
The priory was finally dissolved in 1542. In the English Civil War, the Parliamentary Army built a blockhouse at East Mersea in 1648, with the aim of blockading the River Colne and the besieged town of Colchester. During the 16th and 17th centuries, Dutch and French settlers arrived on the island. Some locals supplemented their income from the oyster trade by smuggling. A police officer for the island was appointed in 1844, and in 1871 a school was opened. The Reverend Sabine Baring Gould (author of "Onward Christian Soldiers" and of "Mehalah", a novel set in Mersea) was Rector of East Mersea from 1870-1881. Mains water and sewerage were available by 1925. In World War II, 2000 troops were stationed on the island to guard against invasion; the island was the Headquarters of the Royal Army Corps Motor Boat Company. Two batteries of 4.7 inch guns were installed; one at East Mersea has been demolished and one at West Mersea, now a cafe. Post war, the island suffered from severe winter weather in 1947 which destroyed much of the oyster fishery, and from the flooding of 1953. Since then the population has increased considerably.
Mersea Island School is a Foundation Primary School for 420 pupils. The earliest part of the school dates back to 1871, with additions in 1980 and 1996. A new hall, kitchen and office have been proposed. Secondary education is provided by Thomas Lord Audley School in Colchester, and Thurstable School in Tiptree.
The island is home to Mersea Island F.C. Who compete in the Essex and Suffolk Border Division 1.
The Mersea Week is a week-long August festival of boat racing. The week of the festival changes each year depending on the tide, in order to ensure a high tide at around midday on the final Saturday.
During the week, starting on Monday, there are races for many boat classes in the Blackwater Estuary, from Optimist dinghies to large yachts. The most celebrated race is the annual "Round-the-Island" race in which some 200 dinghies attempt to sail all the way around the island, helped over the Strood by volunteers.
The Grande Finale Regatta on Saturday includes harbour entertainments, including short spectator inshore races, soot and flour fights on the water, the "Greasy Pole", a firework display and the week's Awards Ceremony. During the day there are street entertainments and food stalls.
In the Greasy Pole event, contenders have to traverse a telegraph pole/mast covered in thick grease and extended out over the water from the deck of the Regatta hosting Thames sailing barge (similar to 'walking the plank'), retrieve the flag at the end Annually a handful of the 50 or so contenders get to the end of the pole and grab the flag 
The island is used as a setting for several works of Margery Allingham, including her first novel, Blackkerchief Dick, published in 1923 when she was 19; Mystery Mile and The Mind Readers. Mehalah is a novel set in Mersea by Sabine Baring-Gould.
- "Westmersea.org". Westmersea.org. 1942-03-19. Retrieved 2013-08-22.
- "Largest Islands of the United Kingdom". users.erols.com. Retrieved 2009-08-30.
- OS Explorer Map, Sheet 184, Colchester, Harwich & Clacton-on-Sea
- "Merseamuseum.org". Merseamuseum.org. 2010-07-16. Retrieved 2013-08-22.
- "Merseacofe.org". Merseacofe.org. Retrieved 2013-08-22.
- Essexcc.gov.uk[dead link]
- "Merseamuseum.org.uk". Merseamuseum.org.uk. 2012-01-24. Retrieved 2013-08-22.
- A Short History of Mersea, Elsie M Karbacz 1999, ISBN 0-9537322-0-7
- [dead link]
- [dead link]
- "The Thomas Lord Audley School | Excellence Through Learning". Tla.essex.sch.uk. Retrieved 2013-08-22.
- "Mersearegatta.org.uk". Mersearegatta.org.uk. 2013-07-27. Retrieved 2013-08-22.