International Date Line International Date Line The International Date Line (IDL) is an imaginary line of demarcation on the surface of Earth that runs from the North Pole to the South Pole and demarcates the change of one calendar day to the next. It passes through the middle of the Pacific Ocean, roughly following the 180° line of longitude but deviating to pass around some territories and island groups. The IDL is roughly based on the meridian of 180° longitude, roughly down the middle of the Pacific Ocean, and halfway around the world from the Greenwich meridian. In many places, the IDL follows
Longitude Act west passage to £5,000 for reaching 110 degrees west or 89 degrees north and £1000 for reaching 83 degrees north. In 1820 £5,000 was paid to the officers and crews of and under this Act. Longitude Act The Longitude Act was an Act of Parliament of the United Kingdom passed in July 1714 at the end of the reign of Queen Anne. It established the Board of Longitude and offered monetary rewards (Longitude rewards) for anyone who could find a simple and practical method for the precise determination of a ship's longitude. The Act of 1714 was followed by a