The restoration of the East Wing of Alexandra Palace was named as one of this year’s RIBA conservation award winners.
The £27million project, which brought the theatre and East Court back to life, won the Royal Institute of British Architects (RIBA) regional awards on Tuesday night.
The theatre reopened in December for the first time in 80 years.
It means it is now in the running for the RIBA national awards, which will be held in June.
Since it opened in December, the theatre has been visited by more than 50,000 people.
Performances by groups from the English National Opera and the Bristol Old Vic have brought in the crowds.
Emma Dagnes, deputy CEO of the Alexandra Park and Palace Charitable Trust said: "We are especially proud that the RIBA judges recognised not only the design of this once in a lifetime project but also the collaborative spirit."
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