Nearly half a million ­journeys have been taken on Edinburgh's tram system in its first month of service.

The controversial service has completed an average of 90,000 passenger trips per week since it launched on May 31.

During the first seven days of operation 130,000 travellers took to the rails and more than 40,000 rode a tram during its first weekend.

A further 24,000 also used the trams on the day of the One Direction concert at Murrayfield.

Tram chiefs said the figures are "in line with ­forecasts" made before the start of the service, which estimated that 4.5 million people would use the trams in its first year.

But they would not state how many of the half million passengers paid the full premium fare.

Tram critic John Carson, a former transport civil ­engineer, said: "The tram is a novelty still and used by day trippers and large numbers of pensioners going for a trip to the airport.

"You cannot judge it without knowing how many concessionary fares are being taken.

"A full picture of the tram's viability and its uptake will not become clear until a full year's service has been passed. The average of 90,000 a week is quite sizeable, but I expect that to depreciate and tail off."