One of the best ways to get around London is by Tube, otherwise known as London Underground. This extensive subway system is a lot cheaper than taking cabs. Consider getting a Visitor Oyster Card before setting off. These plastic smartcards can be used on all Tube lines as well as on buses and on the Docklands Light Railway, and will keep your transportation costs down. You apply online for your Visitor Oyster Card and it’s sent to your home address, anywhere in the world. This means you can use it as soon as you set foot off the plane. You can also buy Travelcards for one day, a week, or a month. These can be used on all public transportation systems in London. A one-week Travelcard gives you seven days' travel for the price of five.