Looking out over beautiful Derwentwater, the winner of this heat will go through to the semi-final and be one step closer to claiming the prize.
The artists are set up along the lake in London's St James' Park, looking out towards Buckingham Palace. They're hoping to create an artwork that catches the eye of judges.
The winner of this heat advances to the semi-final and takes another step closer to the prize - a £10,000 commission for the National Gallery of Ireland.
In the fifth heat, with no pods to protect them, the artists have climbed aboard a WWII warship, HMS Wellington, on the River Thames.