The players visited Faslane last week and experienced a tough military fitness circuit with 43 Commando Fleet Protection Group.
The group also travelled to a nearby firing range where they had the chance to take part in weapons training.
In the afternoon, the Warriors split up into teams and travelled to nearby Loch Lomond where they undertook a physically demanding race on inflatable boats. Later there was the chance wind down with a barbecue in the grounds of Cameron House Hotel.
Event organiser, Captain Steve Hunt RM, training officer at 43 Commando, said: "As elite athletes, the Glasgow Warriors have a lot in common with Royal Marines. Both pride themselves on their high-levels of fitness and self-discipline, and both know that team work and leadership is absolutely critical."
Richie Vernon, the Glasgow Warriors and Scotland centre, said: "It was a really tough day and provided a big challenge for us all.
"Pre-season is so important for us though and I know we'll feel the benefit of days like this once the season is underway."