Clifton Suspension Bridge, Bristol

Described by its legendary engineer Isambard Kingdom Brunel as “my first love, my darling”, it was originally designed to cater for horse-drawn traffic.

Now, more than four million vehicles a year cross the 1,352ft-long toll bridge over the Avon Gorge, a route from Clifton in Bristol to Leigh Woods in Somerset. The £1 toll for every journey pays for its maintenance.

Although similar in size, the bridge towers are not identical in design. They are topped by roller-mounted saddles which allow movement of the three independent wrought iron chains on each side as loads pass over the bridge.

The history of the bridge, dating back to 1864, is kept alive through a programme of tours, events and exhibitions. Its special Hard Hat tour offers the opportunity to go behind the scenes and explore Brunel’s hidden chambers. cliftonbridge.co.uk