Mons Meg is a medieval bombard in the collection of the Royal Armouries, on loan to Historic Environment Scotland and located at Edinburgh Castle in Scotland. It has a barrel diameter of 20 inches, making it one of the largest cannons in the world by calibre.
Mons Meg was built in 1449 on the orders of Philip the Good, Duke of Burgundy and sent by him as a gift to James II, King of Scots, in 1454. The bombard was employed in sieges until the middle of the 16th century, after which it was only fired on ceremonial occasions. In 1680 the barrel burst, rendering Mons Meg unusable. The gun remained in Edinburgh Castle until 1754 when, along with other unused weapons in Scotland, it was taken to the Tower of London. Sir Walter Scott and others campaigned for its return, which was effected in 1829. Mons Meg has since been restored and is now on display within the castle.
Wikipedia https://en.wikipedia.org/wiki/Mons_Meg
Address (Unnamed Road), Edinburgh EH1 2, United Kingdom
Coordinates 55°56'55.636" N -3°12'0.564" E