The Olympic Delivery Authority (ODA) has released aerial images of London's Olympic Park showing construction progress to mark the start of the four-year countdown to the 2012 Olympic Games and Paralympic Games.
The photos show the Aquatics site, which got underway two months earlier than scheduled, beginning to take shape.
Construction on the stadium started in May, three months early. The stadium island now has the clearly defined lower bowl markings of where the main stadium will be built.
According to the ODA, both venues will be ready for test events, with construction and initial overlay work complete by summer 2011.
"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 until the London 2012 Opening Ceremony we are right on track with preparations."
The next stage of building work includes completing the foundations for both venues by next summer. Other milestones include removing the overhead power pylons and starting work on the foundations of the Velodrome and International Broadcast Centre and Main Press Centre.
