More than 3,000 troops are taking part in "Operation Joint Warrior" in and around Galloway Forest in Dumfriesshire.
A group of British and French paratroopers are also carrying out a parachute drop near to the Braid Fell area.
More top news
A look ahead at the Bank Holiday forecast for the Border region.
Cumbria County Council will start work on a £320,000 resurfacing scheme on 6 June, between 6.00pm and 12.30am.
ITV Border's favourite Tapir has left the Lake District Wildlife Park near Keswick, to travel to his new home in the United Arab Emirates.