Have you ever noticed quite how weird Gardner Street in the West End of Glasgow is? It's completely flat for about two-thirds of its length, and then it suddently shoots up at an unrelenting 40 degree angle. This is because it's built on a glacial feature called a drumlin. Drumlins are low rounded hills left behind by a retreating glacier, and Glasgow is built on a whole swarm of them, some more than 60 metres (200 feet) in height, left behind after the last ice age. However, not all Glasgow hills are drumlins. For example, the hill the necropolis is built on isn't a drumlin. Instead is the remains of an extinct volcano, but it too has been sculpted by glacial action, with the ice whittling away the outer rock, leaving just the central plug of solidified magma sticking into the air. So next time you are slogging up one of the city's many hills, just remember you're climbing part of an ancient glacial landscape. It won't make it any easier, but it might just distract you from your efforts for a few minutes!