Mount St Joseph Retreat House is a functionalist modern building that was built in the early 1960s and is strategically located on a higher knoll in Targa Gap. The design is attributed to architect Carmelo Falzon.

Externally the facades of the east and west wings are finished predominantly in local limestone. The central entrance portal that connects the two symmetrical wings is finished in a smooth render and large glazed areas with clever use of terracotta screening where visitors are greeted by an elongated Modernist sculpture of St. Joseph and the infant Jesus by artist Vincent Apap. The building is defined by vertical and horizontal strip apertures framed by thickened continuous limestone reveals further accentuating the directional orientation.

Internally the central entrance and large comfortable circulation area provides access to the east and west wings and contains the internal access stair which retains its original joinery and is flooded in natural light provided by the large vertical strip windows.

The main feature internally however is the pair of patterned glazed double bi-folding passage doors that provide access to the ends of the wings. Fully timber framed and designed to the last detail.

The original ceiling where visible is a series of grid-like exposed reinforced concrete beams giving the appearance of an oversized ‘waffle’ slab structure.

The Malta Environment and Planning Authority scheduled Mount St. Joseph Retreat House as a Grade 2 monument.