The Lightbox was commended for its large scale gallery space
A community gallery, a beach cafe and a restored seaside pavilion have won prestigious architecture awards.
The Royal Institute of British Architects (RIBA) regional award is the third accolade for The Lightbox in Woking, Surrey, which opened last year.
The De La Warr Pavilion restoration in Bexhill-on-Sea, East Sussex, and East Beach Café in Littlehampton, West Sussex, also won the RIBA award.
They were selected from eight shortlisted projects in the South East.
This year 23 buildings were entered from Kent, Surrey, Sussex, Guernsey and Jersey and the finalists were visited by the RIBA Awards jury in March.
The Lightbox gallery, which won the Arts Fund Prize last week, was designed by the creators of the London Eye, Marks Barfield Architects.
The judges were impressed with the size of the gallery space for "large scale three-dimensional work that usually only metropolitan galleries can accommodate" and the "commitment to energy conservation".
The winners have been entered into the national awards in June
The gallery and Littlehampton's East Beach Cafe, designed by Heatherwick Studio, also won regional awards from the Civic Trust in March.
The RIBA judges said the shell-like cafe offered an "engaging maritime narrative".
Their report said: "Like so many other curious relics to be found along the south coast, it is both strange and captivating: weird, but lovable."
The De La Warr Pavilion's £2m restoration project was praised for a decade of "painstaking research, unravelling, consolidating and re-building" carried out by John McAslan and Partners.
The award jury's report said: "The patience of the architects alone is worthy of special mention."
The three winners will go forward for the RIBA national awards to be presented in London on 27 June.