The small oratory dedicated to San Tommaso stands at about one kilometre from the village isolated on a little height. We know little about the historical facts of this chapel, even though the origin of the village is very ancient. Briga is already mentioned in the possessions of the Lords of Biandrate in 1140 and again in 1152 among those of Guido the Great, and then late in the XII century it is included in the parish township of Gozzano. It has a nave with semicircular apse and covered with a masonry semi-dome.’ The façade is saddleback style with added storey; it was built up in 1918 on the occasion of a massive conservative restoration performed by the architect Carlo Nigra, with the laying of a new roof made of beola (a variety of gneiss) slabs. The wall structure of the whole building is composed of heaps of stones, except for some little brick patterns. The frescoes decorating the apse and the triumphal arch and depicting the Virgin Mary and the Apostles, the dove, the Angels and Jesus, among the symbols of the Evangelists are of great interest, as well as the wide belt with geometrical designs, which enclose the apsidal conch, where dark red and green are the key-colours. According to Nigra, these paintings might date back in the XI century and can be considered among the most ancient in Piedmont.