Following a six-year US$25m (€22.5m, £16m) renovation by Ennead Architects, the New York Hall of Science in Queens is celebrating the reopening of its Great Hall.

Originally designed by Harrison and Abramovitz Architects for the 1964/1965 World’s Fair, the Great Hall’s cobalt blue dalle-de-verre glass and concrete walls are designed to give the illusion of being in deep space.

In its original format, visitors to the World’s Fair could see science exhibits and a docking spacecraft hanging from the ceiling. The building has been expanded a number of times, most recently by the team of Schliemann and Ennead –Ennead's former name – in 2004.

As part of the restoration, the 5,400 dalle-de-verre panels were all cleaned by hand, with fifty new panels colour-matched and installed by Willet Hauser Studios, under whose commission the original panels were constructed in 1964.

In addition, the project included stabilisation and repair of the exterior building, renovation and modernisation of the interior of the Great Hall and Great Hall Lobby, and repaving and improvements to the terrace outside the Great Hall.

The reopening was marked with Connected Worlds, the first permanent exhibit to open inside the hall since renovations began in 2009. The immersive exhibit explores the connectivity of the planet and everyone's role in it, and will is the new centrepiece for the Hall.