United Kingdom of Great Britain and Northern Ireland

The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a sovereign country located off the north-western coast of the European mainland. The United Kingdom includes the island of Great Britain, the north-eastern part of the island of Ireland, and many smaller islands. Apart from the land border between Northern Ireland and Ireland, the United Kingdom is surrounded by the Atlantic Ocean, with the North Sea to the east, the English Channel to the south and the Celtic Sea to the south-west. The Irish Sea lies between Great Britain and Ireland. The United Kingdom's 242.500 km² were home to an estimated 66 million inhabitants in 2017.

The United Kingdom is a unitary parliamentary democracy and constitutional monarchy. The current monarch is Queen Elizabeth II, who has reigned since 1952, making her the world's longest-serving current head of state. The United Kingdom's capital and largest city is London, a global city and financial centre with an urban area population of 10.3 million.

The United Kingdom consists of four constituent countries: England, Scotland, Wales, and Northern Ireland. The nearby Isle of Man, Bailiwick of Guernsey and Bailiwick of Jersey are not part of the UK, being Crown dependencies with the British Government responsible for defence and international representation. The medieval conquest and subsequent annexation of Wales by the Kingdom of England, followed by the union between England and Scotland in 1707 to form the Kingdom of Great Britain, and the union in 1801 of Great Britain with the Kingdom of Ireland created the United Kingdom of Great Britain and Ireland. Five-sixths of Ireland seceded from the UK in 1922, leaving the present formulation of the United Kingdom of Great Britain and Northern Ireland. There are fourteen British Overseas Territories, the remnants of the British Empire which, at its height in the 1920s, encompassed almost a quarter of the world's land mass and was the largest empire in history. British influence can be observed in the language, culture and political systems of many of its former colonies.

The United Kingdom was the first country that issued postage stamps, back in 1840. Being the first, they do not have to put their country name on the stamps like the rest of the world. All stamps have either the portrait or the monogram of the ruling monarch.

The stamp I put on the envelope, international tariff, is part of a series of definitives that started on 5 June 1967. After being cancelled at the Trafalgar Square Post Offce the envelope was put through the normal channels and thus received a second cancellation from the machine in the Mount Pleasant mail centre.

Website of Royal Mail: royalmail.com/stamps-collectibles-gifts.

Date sent: 14 April 2017

Date postmark: 21 April 2017

Date received: 25 April 2017

Number of days: 11

Envelope in collection: 13