The first bridge across the Thames in London is thought to have been built by the Romans around 40AD, although Channel 4's Time Team might dispute that.
In 1825 work began on the first tunnel under the river, between Rotherhithe and Wapping. This enormous engineering project took 18 years to finish, opening in 1843. Today it's used as part of the overground (although it's under the ground) rail network.
Before too long, there may even be a cable car zipping to and fro over the Thames, which would be a first for the capital's waterway.
Another way to get from one side to the other without getting wet is by using the Greenwich Foot Tunnel. There can't be many people who can say they've walked under one of the world's great rivers – the Greenwich foot tunnel gives you the chance!
The Greenwich foot tunnel links the Isle of Dogs and Greenwich, and was built more than a hundred years ago. The idea was that it would replace the then unreliable and pricey ferry service, allowing workers living south of the river easy access to their workplace north of the river, in the docks and shipyards.
These days many people use it to go the other way, across to Greenwich, where you have the Royal Observatory, the Cutty Sark, the National Maritime Museum and the Royal Naval College.
You could take the Docklands Light Railway from Bank station to Island Gardens station. The entrance to the foot tunnel is a short distance from Island Gardens station – look out for the distinctive glass dome building.
Though the tunnel is spacious (with a diameter of just under three metres), it may not be the best way to cross the Thames if you get a bit claustrophobic. Lifts operate at set hours, taking you down (or up) 15 metres. There are also stairs.
The length of the tunnel is 370 metres and it's open 24/7, so if you wake up at three in the morning with a sudden urge to walk under water, you know the place to go. Alternatively, there's also the Woolwich foot tunnel, slightly further upriver.