Four hundred people were trapped on the London Eye for more than an hour while engineers fixed a mechanical fault, a spokeswoman for the riverside tourist attraction said on Tuesday.
Sightseers were suspended up to 450 feet (137 metres) above the ground on Monday night as workmen repaired one of the four huge tyres that turn the observation wheel.
Staff spoke to visitors over an intercom system fitted in each of the 32 glass pods. They were offered water, blankets and glucose tablets stored in "comfort packs".
"It stopped for a brief period while we rectified it and then we got all the guests off," said a London Eye spokeswoman. "We had full communication with them throughout and offered them a refund afterwards."
The wheel, which can carry 800 passengers during each 30-minute revolution, reopened at 10 am on Tuesday.
Since it opened in 2000, the attraction has become one of London's best-known landmarks, with about 3.5 million visitors each year.