Tractor Trailer Guided Tours Take a 45 minute Tractor Trailer Guided Tour to the 'out of bounds' part of the site. You will see the remains of buildings used in the production of explosives including the Grand Nitrator (where nitroglycerine was manufactured), Newton’s Pool used for the testing of underwater explosives including the explosives used in the Dambusters' “bouncing bomb” and our iconic Press House with waterwheel and press where one of the most dangerous processes on site took place. Tractor Trailer Guided Tours run on our Experience the Royal Gunpowder Mills days and can be booked for Group Visits. Manage Cookie Preferences