Barca (Latin), also known as Barke, Barka, Barqa, Barqah, and Barce was an ancient, medieval, and early modern city located at the site of Marj in northeastern Libya. It remains a Roman Catholic and Orthodox titular see.

Marj, El Merj in Benghazi and Egyptian Arabic, is a city in northeastern Libya and the administrative seat of the Marj District. It lies in an upland valley separated from the Mediterranean Sea by a range of hills, part of the Jebel Akhdar Mountains, and is generally believed to be the site of the ancient city of Barca.