One of the founding works of the museum’s collections is a large mosaic unearthed at Bergheim in 1848. This work originally covered a surface of 80 square meters, but only an eighth of it has survived. Initially displayed in the choir of the Unterlinden convent’s former chapel, today it is presented on the basement level of the museum, in a room devoted to the Roman period. It is a polychrome floor mosaic, its motifs reminiscent of a highly ornate rug. A two-strand plait frames its complex composition, mainly including geometric motifs, with the occasional naturalistic figure: nine circles inscribed within four-lobed squares alternate with eight squares inscribed within curvilinear quadrilaterals and eighteen small squares with concave sides. All of these motifs are themselves bordered with a two-strand plait design. The density of the decoration is typical of the workshops in the region of Trier, in the 3rd century AD.