Final answer:
Constantinople, the capital of the Byzantine Empire, was located on the Bosphorus strait, connecting the Black Sea with the Mediterranean.
Step-by-step explanation:
The capital city of the Byzantine Empire, Constantinople, was located on the Bosphorus strait, which connects the Black Sea and the Mediterranean Sea. Constantinople served as a pivotal center for trade, governance, and culture from its foundation by Emperor Constantine in 330 CE. Renamed Istanbul after the Ottoman conquest in 1453, this city has historically been a bridge between Europe and Asia and a node of significant economic and cultural flux due to its strategic position on trade routes, including the Silk Road.