Rathlin Island is an island

Island

An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, cays or keys. An island in a river or lake may be called an eyot , or holm...

 off the coast

Coast

A coastline or seashore is the area where land meets the sea or ocean. A precise line that can be called a coastline cannot be determined due to the dynamic nature of tides. The term "coastal zone" can be used instead, which is a spatial zone where interaction of the sea and land processes occurs...

 of County Antrim

County Antrim

County Antrim is one of six counties that form Northern Ireland, situated in the north-east of the island of Ireland. Adjoined to the north-east shore of Lough Neagh, the county covers an area of 2,844 km², with a population of approximately 616,000...

, and is the northernmost point

Extreme points of the United Kingdom

This is a list of the extreme points of the United Kingdom: the points that are farther north, south, east or west than any other location. Traditionally the extent of the island of Great Britain has stretched "from Land's End to John o' Groats" .This article does not include references to the...

 of Northern Ireland

Northern Ireland

Northern Ireland is one of the four countries of the United Kingdom. Situated in the north-east of the island of Ireland, it shares a border with the Republic of Ireland to the south and west...

. Rathlin is the only inhabited offshore island in Northern Ireland, with a rising population of now just over 100 people, and is the most northerly inhabited island off the Irish

Ireland

Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

 coast. The reverse L-shaped island is 4 miles (6 km) from east to west, and 2.5 miles (4 km) from north to south. The highest point on the island is Slieveard, 134 metres above sea level.