The largest city and capital of the prefecture is Tripoli, with a population of 30,090 inhabitants, which is spread over an extensive plateau in the center of the Peloponnese, which is at an altitude of 650 m and is surrounded by the mountains of Artemisio, Partheni, Parnon and of Mainalos. Other important cities of Arcadia are Megalopolis, Leonidio, Astros, Tyros, Levidi. In the past, particularly important settlements were the main villages of Dimitsana, Lagadia, Vytina, Tropaia, Prastos and Karytaina.

The most important ports of Arcadia are Paralio Astros, Tyros and Plaka Leonidio.