West Mersea beach
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 an island in Essex, England, to the south of Colchester. It is situated in the estuary area of the Blackwater and Colne rivers. The island is connected to the rest of England by The Strood, a causeway. Its name comes from the Old English meresig, meaning "island of the pool".
The island has been inhabited since pre-Roman times and the church of St Peter & St Paul in West Mersea is thought to have existed since the 7th century. Today it is a popular destination for sailing and other watersports and has a regular boat racing festival in August.
The island the most easterly inhabited island in the United Kingdom, 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). It is formed by the Pyefleet Channel to the north and the Strood Channel to the west connecting the Blackwater to the Colne. The much smaller Ray Island lies adjacent to the north of the island. 
Internally, it is split between West Mersea, which is the main inhabited area containing the jetty and marina, and East Mersea, which is predominantly farmland. There is also a small hamlet at Barrow Hill to the north of West Mersea. The land immediately facing the Blackwater is mostly beach, and the former Bradwell Power Station can be seen on the other side.
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 main industries on Mersea are farming, fishing (including oyster gathering), and servicing the leisure boating industry. The Company Shed restaurant on the west side of the island serves seafood fresh to order and has been praised for its quality by Jamie Oliver.
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.
Evidence has shown a number of fishtraps around the island, which date from around the seventh century. The Anglo-Saxons built the church at West Mersea (St Peter & St Paul) which may have been founded around this time. 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 here was granted to the Abbey of St Ouen in France by Edward the Confessor in 1046. The priory survived until the dissolution of the monasteries 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. Some ruins of this blockhouse remain and are known as the Block House Stone. 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.
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