Menai Suspension Bridge - world's first modern suspension bridge

Construction of the bridge began in 1819 with the concrete towers on either side of the strait. Then came the sixteen huge chain cables, each made of 935 iron bars that support the 176 metre span. To avoid rusting, each cable was first soaked in linseed oil. The bridge was opened to much fanfare on January 30, 1826, and succeeded in reducing the 36 hour journey time from London to Holyhead by 9 hours.

The bridge was not the first suspension bridge, but was so hugely greater than anything previously built that it is considered the world's first modern suspension bridge.