Developer Reef Group (London) is planning to transform Cavendish Square, a public garden square in London, into a subterranean mixed-use health and wellness hub.

The hub will feature clinical, spa, and fitness facilities, as well as restaurants, bars and retail spaces. The development is intended to expand the footprint of the Harley Street Medical Area collective of independent hospitals, clinics, and specialists, with additional space for specialist healthcare facilities.

The 280,000-square-foot project will include four stories below ground level, with entrances located on Oxford Street, Regent Street, and Harley Street. The project will feature doughnut-shaped floors of up to 80,000 square feet and floor-to-ceiling heights of up to 26 feet, with light wells and internal atria drawing natural light to the floors below.

In addition to developers CBRE (London) and Savills (London), other project team members include UrbanR (architecture), Gensler (design; London), and Sonnemann Toon (architecture; London).

Construction is expected to start next year with completion in 2023.