This six-tonne siege gun is what cutting edge military technology once looked like. Mons Meg could fire a 150kg gunstone for up to 3.2km (2 miles). She was one of a pair of giant iron cannons given to James II in 1457 by Duke Philip the Good of Burgundy. Her name is taken from the Belgian town of Mons, where she was made in 1449 – at a cost of 1,536 pounds and 2 shillings. ‘Meg’ was added only later, in the 17th century.

Mons Meg was so heavy that even a team of oxen couldn’t move her more than 5km (3 miles) a day. So it was quite a feat when, in 1460, James II had her hauled 80km (50 miles) to the siege of Roxburgh Castle. But the unlucky king was killed there when another of his cannons exploded.

James IV put Mons Meg back in action, first to attack Dumbarton Castle (in 1489) and then Threave Castle and Norham Castle (both in 1497). She ended her fighting days in James V’s navy, retiring around 1550. Oliver Cromwell would later refer to the gun as the “great iron murderer called Muckle Meg” when he captured Edinburgh Castle in 1650.

When Mary Queen of Scots married in 1558, Mons Meg fired a gunstone over the city in celebration: it landed in what is now the Royal Botanic Garden. She fired her last salute in 1680, to mark a visit to Edinburgh by James Duke of York. Her barrel finally burst in 1681.

Mons Meg spent 75 years in England, on display at the Tower of London. The Tower’s 1821 guide said of the cannon, “it is of such amazing dimensions that a man may go into its mouth”. She made her welcome return to Edinburgh Castle in 1829. Cavalry and infantry escorted her from Leith Docks to Castle Rock.

A new timber and iron carriage was made for the gun in 1934. Mons Meg is on loan from the Board of Trustees of the Royal Armouries.

Edinburgh Castle

Edinburgh Castle has witnessed many of the defining events in Scotland’s history. Sieges were fought over the mighty stronghold. Royalty lived and died within its walls. Just the sight of the Castle Rock has terrified and inspired countless generations.

Fierce Iron Age warriors defended a hill fort here, and the nation’s oldest poetry tells of a war band feasting here for a year before riding to their deaths in battle.

The castle’s royal connections go back 1,000 years, and the city’s oldest building stands on the site. David I built St Margaret’s Chapel around 1130, as a tribute to his devout mother.

Edinburgh has been besieged more than any other castle in Europe, and the Scots and English struggled over its control during the Wars of Independence. In 1314, Thomas Randolph, a relative of Robert the Bruce, led a daring night raid to reclaim it from the English.

Over the last 200 years, Edinburgh Castle has become a national icon. Today it is Scotland’s leading tourist attraction and a chief element of the Old and New Towns of Edinburgh UNESCO World Heritage Site.

Home of royalty

Scottish monarchs commissioned grand buildings here – both as secure lodgings and to show off their wealth, power and good taste. The castle’s royal role continues today.

Monarchs who sheltered here include:

  • Queen Margaret (later St Margaret), who died here in 1093
  • Mary Queen of Scots, who gave birth to James VI in the Royal Palace in 1566

Edinburgh was among Scotland’s chief royal residences during the 1400s and 1500s.

Bonnie Prince Charlie – Mary’s great-great-great grandson – captured Edinburgh but failed to take the castle during the 1745–46 Jacobite Rising.

Army headquarters

Edinburgh Castle became more important as a military base from the late 1500s onwards.

After the ‘Lang Siege’ of 1571–3, the castle’s military strength was repaired, maintained and improved. Additions included:

  • the distinctive Half Moon Battery
  • a huge garrison
  • a secure jail for prisoners of war

The military presence remains unbroken – Edinburgh Castle is still an active base today. It also houses three military museums, the Scottish National War Memorial and the Prisons of War exhibition.

Find out more about Edinburgh Castle


Date Made
l 4064mm (l 160")
Property Information
Edinburgh Castle
Object Number
Access Status