Mono is a department in southwestern Benin bordering Togo. It is bounded to the northeast by Zou Department, to the south by a maritime coastline of approximately forty kilometers (40 km) on the Atlantic Ocean; to the east by a succession of bodies of water formed by the Couffo River valley, Lake Ahémé and the Toho River, which constitute its border with Atlantique Department, and to the west by Togo with 90 km of natural border formed by part of the Mono River. It has a population of 495,307 inhabitants (2013), a density of 309 inhabitants/km², covering 160,500 hectares or 1,605 km². The inhabitants of Mono are primarily Aja, Fon, Xwla, Mina, Sahouè, Kotafon or Ayizo peoples. Since 2013, Mono Department has comprised 400 villages and city quarters. Mono's Communes Athiémé, Bopa, Comè, Grand-Popo, Houéyogbé and Lokossa (the prefecture) are the six (6) communes of Mono. This department is characterized by a dense hydrographic network offering opportunities for innovative tourism experiences. Notable attractions include vast beaches lined with coconut palms, the semi-lacustrine village of Guézin. The thermal springs of Possotomé and Bopa on the western shore of Lake Ahémé provide opportunities for thermal spa getaways. The Bopa Belvedere offers stunning views over Lake Ahémé; Bouche du Roy is a natural wonder combining a beautiful beach sheltered by coconut palms with the dramatic spectacle of the Mono River meeting the Atlantic Ocean