New aerial shots of the Olympic Park in London have been released to mark four years to go until the opening ceremony.
The photos show the Aquatics site following the start of construction last week. The stadium island now shows the outline of the main stadium and the lower bowl taking shape. Construction started three months early on the stadium in May and two months early on the Aquatics Centre last month.
Both venues will be ready for test events, with construction and initial overlay work complete, by summer 2011.
The photos include shots taken of the Park last year to show the scale of change over the past few months.
ODA chief executive David Higgins said: "These new images clearly show the good rate of progress we are making with work now well underway on both the Main Stadium and Aquatics Centre.
"With four years to go [from yesterday] until the London 2012 Opening Ceremony we are right on track with preparations."