The Peloponnese (ˌpɛləpəˈniːz,_-ˈniːs), Peloponnesus (ˌpɛləpəˈniːsəs; Pelopónnēsos, peloˈponisos), or Morea is a peninsula and geographic region in southern Greece. It is connected to the central part of the country by the Isthmus of Corinth land bridge which separates the Gulf of Corinth from the Saronic Gulf. From the late Middle Ages until the 19th century, the peninsula was known as the Morea (Μωρέας, Morèas), a name still in colloquial use in its demotic form (Μωριάς, Moriàs).
The peninsula is divided among three administrative regions: most belongs to the Peloponnese region, with smaller parts belonging to the West Greece and Attica regions.
The Peloponnese is a peninsula located at the southern tip of the mainland, in area, and constitutes the southernmost part of mainland Greece. It is connected to the mainland by the Isthmus of Corinth, where the Corinth Canal was constructed in 1893. However, it is also connected to the mainland by several bridges across the canal, including two submersible bridges at the north and the south end. Near the northern tip of the peninsula, there is another bridge, the Rio–Antirrio bridge (completed 2004). Indeed, the Peloponnese is rarely, if ever, referred to as an island.
The peninsula has a mountainous interior and deeply indented coasts. The Peloponnese possesses four south-pointing peninsulas, the Messenian, the Mani, the Cape Malea (also known as Epidaurus Limera), and the Argolid in the far northeast of the Peloponnese. Mount Taygetus in the south is the highest mountain in the Peloponnese, at . Οther important mountains include Cyllene in the northeast (), Aroania in the north (), Erymanthos () and Panachaikon in the northwest (), Mainalon in the center (), and Parnon in the southeast (). The entire peninsula is earthquake prone and has been the site of many earthquakes in the past.
The longest river is the Alfeios in the west (), followed by the Evrotas in the south (), and also the Pineios, also in the west ().