Vintage Real Photo Postcard. Caption reads "Constanta. Plajea Mamaia." Studio Fotographic No.3. The image depicts a beach resort area. Divided back, unused. Condition: Very good condition. Comments: Constanta, historically known as Tomis, is the oldest still-populated city in Romania. It was founded around 600 BC. The city is located in the Dobruja region of Romania, on the Black Sea coast. It is the capital of Constanta County and the largest city in the region. Constanta is the fifth most populous city in Romania. The Port of Constanta has an area of 39.26 km2 (15.16 sq mi) and a length of about 30 km (19 mi). It is the largest port on the Black Sea, and one of the largest ports in Europe.