The Docklands Light Railway serves London City Airport.
The Docklands Light Railway has frequent services between Bank station, in the heart of London's financial district, Canning Town and London City Airport. The DLR also serves Canary Wharf.
Trains run approximately every 10-15 minutes. Journey time between London City Airport and: Canning Town is 7 minutes; Canary Wharf 20 minutes; Bank 22 minutes.
The fare to/from: Bank is £4.30 one-way, or to save money get a pre-paid Oyster card.
More information is available at the Transport for London web site.