This year’s festival theme is a celebration of the life and works of civil engineer Sir Benjamin Baker.
A Frome man born and bred, he became one of the greatest engineers of his age the Forth Bridge being one of his many accomplishments.
The beer, named Iron Brew, is a new real ale and has an ABV of 4.1 per cent.
Charlie Thomas, manager of the Griffin pub, which is attached to the Milk Street Brewery, said: “The beer is a full-bodied amber ale with hops.
“It has been brewed to celebrate the visionary genius of the Frome engineer.”