PERMISSION REQUIRED Castle Cement do cater for group visits arranged on prior notice basis, normally outside the working hours of the quarry which generally operates 7am - 3pm Monday to Friday. Any enquiries to arrange visits should be addressed to the Quarry Manager at Ketton Works location address. Castle Cement Ltd, Ketton Works, Ketton, Stamford Lincolnshire, PE9 3SX   (Ketton Quarry organised trip) - 2003 Ketton Quarry is too big to completely cover in one trip, it is several miles wide and is still growing. The best area to search in is the Blisworth Limestone, part of the Oolite series. Both the Great and Inferior oolite is present at Ketton Quarry. The best area to go is to follow the track around to the right past the vehicles from the continue area, then turn left and follow the track round and up a steep hill so that you are at the Left end of the quarry from the entrance. Follow it down to the end and the Blisworth Limestone starts ahead of you. Ammonites can be found, but shells, corals, echinoids and sharks teeth and bones are more common. Dinosaur footprints are also quite common along with fragments of bone. (Ketton Quarry) - 2003