Make your first real stop either
St. Paul's Catacombs or
Domvs Romana, not both at once. The catacombs on
Triq Ħal Bajjada give you scale, burial culture, and atmosphere;
Domvs Romana near
Wesgħet il-Mużew gives you mosaics, Roman domestic life, and an easier indoor start. Choose the first mood you want, then let the rest of
Rabat unfold around it.