Within a splendid blue Modernista building, decorated with white checkerboard designs, lies Tortosa's modern, minimalist town museum. The 1908 building is worth ogling: formerly a city slaughterhouse, its design has delicate Moorish elements. Within, the museum does a great job of contextualising the area's history, from traces of early Iberian settlement to Roman rule, Moorish times and the devastation of the Spanish Civil War.
Displays are mostly in Catalan; pick up an audio guide (€1).
It's in the same complex as the tourist office.