Working on a project that would be a world’s first, developers in London are planning a swimming pool suspended high between two buildings, with a clear shell that enables swimmers to feel like they’re in the sky.

The 25-meter-long pool would connect two apartment complexes that are part of the 2,000-home Embassy Gardens development in London’s new Nine Elms quarter, according to Dezeen .

Architecture firm Arup Associates, structural design engineers at Eckersley O’Callaghan, and aquarium design firm Reynolds came together on the ambitious project.

Already in the second stage of construction, developers say it will include both a bar and a spa.