The Koper Regional Museum is housed in the Belgramoni-Tacco Palace, a handsome 17th-century mansion on a quiet street in the old town. The museum's collection covers the history and culture of the Slovenian Littoral (Primorska) region from prehistoric times through the 20th century, with particular strengths in the Roman period, Venetian-era art, and the complex recent history of a region that changed national identity multiple times in the 20th century.
The painting collection includes works by Venetian masters and Slovenian artists from the 18th and 19th centuries. The Roman and medieval archaeological sections display material excavated from Koper and the surrounding area. The ethnographic collection documents traditional life in the villages of the Slovenian Karst.
The museum is small by national standards but well maintained and honestly curated. Allow an hour. The building itself is part of the experience — the palace's courtyard and the proportions of the rooms give a good sense of how prosperous Venetian families lived in their Adriatic towns.