The Royal Edinburgh Military Tattoo - a special show held at Edinburgh Castle - is back for its 69th year.
It is a huge military spectacle, which showcases musical performances and cultural acts from across the world.
The British Army takes centre stage at the event, but it showcases other military groups too.
Read on to find out more about where it came from and what's happening at this year's event.
The first Royal Edinburgh Military Tattoo was held in 1950 and was far from the huge event that it is today.
It all started when the British Army performed at the Edinburgh Festival the year before, in 1949.
Soldiers performed a show called Something About a Soldier at the Ross Bandstand in Princes Street Gardens, just below Edinburgh Castle. (It's still there today if you want to go to visit it!)
But Lieutenant Colonel George Malcolm wanted the army to contribute more to the Edinburgh International Festival - and so the Military Tattoo was started a year later. It would go on to become its very own annual spectacle.
From a modest event in a park to today's global showcase at the Castle
Two years after it first began, non-British military forces became involved with it too, when regiments from Canada, France and the Netherlands took part.
In 1968, colour televisions were big news, and the Tattoo was beamed to people in their homes in colour for the very first time.
To this day, over 46 different countries have been involved and the event is famous all across the world.
The term 'Military Tattoo' comes from the 17th-Century Dutch phrase 'doe den tap toe', which means 'turn off the taps'.
It was used to tell soldiers on a night out to go back to their barracks!
This year, the Tattoo runs from 2 to 24 August.
The theme for 2019 is kaleidoscope, because this was a device invented by Scottish scientist Sir David Brewster back in 1816.
Around 220,000 thousand people are expected to come together for a display full of lights, music and colours.
It will feature performances from China, France, Germany, New Zealand, Trinidad and Tobago and Africa.