The UK is leading NATO's enhanced forward presence in Estonia as its allies and partners take part in Exercise Spring Storm.
This year, the exercise consists of more than 9,000 troops from 17 allied nations, including 1,000 British soldiers.
They are operating around 15 kilometres from the Russian border.
The Estonian 1st Infantry Brigade and 2nd Brigade were split into groups to conduct a range of scenarios, which involved exercising in civilian populated towns and rural environments.
There are currently 800 British troops deployed in Estonia.
Lieutenant Colonel Angus Tilney, the Commanding Officer of the Kings Royal Hussars said the exercise is an "amazing opportunity”.
Lt Col Tilney said: "Its been fast and furious.
"Working on open streets, towns and roads of Estonia is a unique experience.
"I've never done anything like it before in 18 years of an Army career."
Armed Forces Minister, Mark Lancaster was 'impressed' with the involvement of British personnel, having visited them as they completed the first half of the exercise.
"To see the ability of our troops within a NATO context training together is really powerful.
"I think the presence we have here is really important," Mr Lancaster said.
During his visit, Mr Lancaster promised Britain's military presence would remain in Estonia for the "foreseeable future".
But he told Forces News the exercise was not being used to antagonise Russia.
"This is not a provocation," he said.
"This is simply a deterrence and NATO is a defensive organisation and it’s right that we should be able to exercise with our allies."
Ground forces will also be supported by RAF Typhoons, UK Wildcats and Apaches.
It's the largest exercise conducted by the Estonian Defence Force, and it's used to give a snapshot of how the force operates.
General Indrek Sirel, the Deputy Chief of Defence for Estonia, who organised the operation said: "This exercise is an important part of our annual training cycle.
"We are training all the elements of which the Estonian Defence Force consists of."
These elements included how the force communicates and operates with allied partners.