The appeal of the church of Sant Pèir lies above all in the architectural and sculptural vestiges of its Romanesque past: the structure of the nave, the facade and the baptismal font.

All that remains of the nave's Romanesque structure is the masonry and semicircular vault.
The facade of Sant Pèir d'Escunhau, which, along with its baptismal font, is its most outstanding attraction, is based on three decreasing arches and two archivolts sustained by columns. In the centre of the tympanum there is a sculpted figure of Christ, similar to those that can still be seen in the narthexes Sant Miquèu de Vielha and Sant Martin de Gausac. The rest of the facade is decorated with different sculptural elements, such as the capitals, with anthropomorphic representations the chequered pattern, a recurring decorative resource in the churches of the Aran valley and the lintel which crowns the architectural body of the facade, comprising a Christ's monogram flanked by two enclosed eight-point stars.

The baptismal font features a sculpted iconographic language which relates it to the baptismal font of Gausac and even of Casau. It alternates vegetable and geometric motifs with highly symbolic figurative representations; they are of very linear design and date from the 12th and 13th Centuries. The Gothic period's influence can be appreciated in the internal structure of the church, supported on ribs and ribbed vaults, as well as in the outside window, located in the head of the south wall.
The current belfry was added to the church between the 17th and 18th Centuries.