The MNHA on the Marché-aux-Poissons covers Luxembourgish material culture from prehistory to the present. The strongest section is the Gallo-Roman, with the floor mosaics from Vichten as the headline piece — a startlingly intact Roman pavement showing the nine Muses, lifted intact from a Roman villa in 1995 and reassembled in a purpose-built gallery.
Allow two to three hours. The upper floors hold a respectable European painting collection, and the museum café in the inner courtyard is one of the few quiet spots in the old town for lunch.