The Isle of May is located in the north of the outer Firth of Forth

Firth of Forth

The Firth of Forth is the estuary or firth of Scotland's River Forth, where it flows into the North Sea, between Fife to the north, and West Lothian, the City of Edinburgh and East Lothian to the south...

, approximately 8 km (5 mi) off the coast of mainland Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

. It is 1.8 km long and less than half a kilometre wide. The island is owned and managed by Scottish Natural Heritage

Scottish Natural Heritage

Scottish Natural Heritage is a Scottish public body. It is responsible for Scotland's natural heritage, especially its natural, genetic and scenic diversity. It advises the Scottish Government and acts as a government agent in the delivery of conservation designations, i.e...

 as a National Nature Reserve.

Most visitors to the island are daytrippers taking the ferry from Anstruther

Anstruther

Anstruther is a small town in Fife, Scotland. The two halves of Anstruther are divided by a small stream called Dreel Burn. Anstruther lies 9 miles south-southeast of St Andrews. It is the largest community on the stretch of north-shore coastline of the Firth of Forth known as the East Neuk,...

 in Fife

Fife

Fife is a council area and former county of Scotland. It is situated between the Firth of Tay and the Firth of Forth, with inland boundaries to Perth and Kinross and Clackmannanshire...

, although up to six visitors can stay at the observatory, usually for a week at a time.