Slideshow: this underground house by London studio De Matos Ryan tunnels beneath a listed stone tower in Gloucestershire, England.

A grass roof slopes up to cover living and utility rooms inside the single-storey building but cuts away at the centre to create a concealed courtyard.

A corridor leads from the main house into the tower itself, where a games room occupies the ground floor and bedrooms are located on two floors above.

Glazed walls at the rear of the house face out onto a sunken terrace and swimming pool.

This is the second project we've featured this week in Gloucestershire - see our earlier story about a school with a shiny copper chapel.

Photography is by Edmund Sumner.

Here's some more text from De Matos Ryan:

The Round Tower, Gloucestershire
De Matos Ryan

The Round Tower is a Grade II Listed folly, which had been reduced to ruin by years of neglect and fire.

Located on the crest of a hill overlooking Siddington Village, the exposed site is visually integral to the setting of this listed structure.

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As such the design approach maintains the open relationship with the surrounding agricultural landscape by developing a discreet and substantial underground extension to the tower.

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This underground extension provides the main open plan living spaces and is lit by both a central open sunken courtyard and a lateral ‘landscape scoop’ concealing the new swimming pool and associated sun terraces from public view.

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The listed tower remains clearly the dominant structure, providing the front door to the 4 bedroom family house and the means of vertical circulation. It is also the visual focus of the main sunken courtyard garden.

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The restored tower provides additional accommodation and a roof terrace for the enjoyment of the panoramic views of the surrounding landscape.

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A new detached building adjacent to the entrance to the site, provides garaging and an additional guest studio.

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