On foot
Once in the City, its small and compact nature means travelling on foot between attractions is possible and advised. You can quite easily get lost and miss out interesting features if new to the City. The street pattern is particularly chaotic in some parts being medieval and unplanned and there are many fun shortcuts and routes that take you away from main roads. Buy and bring a detailed map!
From The Airport
Underground services are connected to all major London airports, as well as Express train services that take you directly to some of the main stations in the centre of London. (http://www.britainexpress...)
By ship
An increasingly popular way of travelling through London, by both tourists and residents, is by boat on the Thames itself. The City can has two piers from which regular services operate to and from: Blackfriars Millennium Pier in the west or Tower Millennium Pier in the east.
Barbican
Blackfriars to/from Gatwick and Luton airports, Cannon Street closed Sa, Su and public holidays, City Thameslink to/from Gatwick and Luton airports, no tube, Fenchurch Street tube: Tower Hill, Liverpool Street to/from Stansted Airport and Moorgate. All also tube stations except City Thameslink and Fenchurch Street.