The series is a dramatisation of Dava Sobel's 1995 book of the same title, adapting the true story of the marine chronometer.

Longitude was written and directed by Charles Sturridge.

The drama was co-produced by Granada Television and the A&E Network for Channel 4, and first broadcast in the UK on Channel 4 and in the US on A&E in early January 2000.

Michael Gambon plays clockmaker John Harrison, while Jeremy Irons plays horologist Rupert Gould, interweaving the 18th-century and early 20th-century storylines.

In 2001, Longitude received ten British Academy Television Award nominations and won five, including Best Actor for Michael Gambon and Best Drama Serial.