Cornet Iain Little will be at the centre of events, along with his Right and Left hand men Stuart Murray and Simon Tweddle.
He will accept the flag in the town centre at 8.30 am and will then lead the cavalcade around the historic boundaries.
The retinue will return to gallop up the Kirk Wynd at approximately 9.15 am.
The next highlight takes place at noon and is the chase.
Focus in the afternoon switches to the field, where there will be sports, flapping and highland games.
Thousands of people are expected to turn out to watch and enjoy the festivities.
And police have reminded motorists locally that the A7 will be closed twice during the day due to the event: firstly from 7.30 am to 12 noon and again between 8-10 pm.
Meanwhile, a large crowd turned out on Castle Craig Day at the weekend – pictured above – to watch the horses gallop up the Kirk Wynd and steep slopes of Mount Hooley.
After heading to the Castle Craigs, the mounted procession eventually made its way to Cronksbank to be welcomed by a large crowd who had made their way by vehicles and on foot.
On arriving back in Langholm, the riders were met at the Townfoot by the pipe band who played them through the streets.
The Castle Craigs function took place in the Crown Hotel in the evening when new members received badges. After speeches, members of the town band entertained and the evening continued in a social capacity.
There was a collection for the band which raised £283.
