US four-time Olympic gold medallist Michael Johnson ran around Stonehenge with the London 2012 flame at sunrise Thursday in what he called a "magic" moment.
The retired sprinter, who still holds the 400 metres world and Olympic records, carried the torch around the prehistoric monument in Wiltshire, southwest England, famed for its circle of large standing stones.
Johnson was on Salisbury Plain at 5:07am to take the flame around the site, before going on to get the day's torch relay started outside Salisbury Cathedral.
"It was a great experience to carry the torch around the iconic Stonehenge," Johnson, 44, said afterwards, 15 days ahead of the start of the Games.
"This was incredible, just a really incredible, magic moment."
Thousands of revellers turn up annually at Stonehenge on June 21 to witness the summer solstice, when the rising sun appears between the stones in alignment.
The torch relay is on the 55th day of its 8,000-mile (12,875-kilometre) journey around Britain.
Johnson said he was looking forward to the Olympics, which officially open on July 27.
"The competition on the track should take care of itself and I think London will do a great job of hosting the Games," he said.
The relay is taking the Olympic flame within an hour's travel time of 95 percent of the British population, taking in famous sports venues, historic sites and places of outstanding natural beauty.
London Mayor Boris Johnson on Thursday declared the Olympic Park in Stratford, east London, "ready to receive the world".
However, concerns remain over security and border controls.
The government admitted Wednesday it was having to provide an extra 3,500 troops to protect Olympic venues after the contracted private security firm was unable to supply enough guards.