The name Samsø is of unknown origin. The name is known from 1075 as Samse. The word is a simplex and the -ø ending is thus a later transformation, indicating that the name Samsø is not related to the Danish word and letter 'ø'.
Ballen's beach and village are popular with visitors. The island is served by a bus service which runs around the island, including the two ferry terminals in Sælvig and Ballen. In clear weather, the peninsula of Helgenæs to the north is visible. Geographically, the island divides into three areas:
The North Island is divided from the South Island by the artificial Kanhave canal. Here a larger part of the countryside is uncultivated and it presents a wavy landscape of meadows and small patches of woodland and heath. Like the rest of Samsø, the coastline is characterized by steep cliffs and stony beaches, with some sandy beaches in between suited for bathing. Issehoved is Samsø's northernmost point and presents what have been described as a miniature of Skagens "Grenen". The small towns of Nordby, Mårup and Langør is situated on the North Island. Just north of Nordby is the worlds biggest permanent labyrinth named 'Labyrinten', founded in the year 2000. It comprise a 60,000-square-metre (645,835-square-foot) patch of conifer woodland, grown on a previous christmas tree plantation. Northwest of Nordby, is the hill of Ballebjerg, Samsøs highest point, reaching 64 m. Near the village of Mårup is the harbour of Mårup Havn. In the summer months (17 June to 22 August) the old wooden freight-ship M/S Tunø, ferry passengers back and forth from here to the island of Tunø just west of Samsø, two days a week. Other two days of the week, the same boat is offering seal-safaris from Langør at Stavns Fjord.
The shallow lagoon of Stavns Fjord, houses most of the smaller islands of Samsø municipality. The largest of them is Hjortholm and most of the rest are just small islets really, but have been named individually. The lagoon is separated from the sea of Kattegat by the 7 km long sandbar of Besser Rev. It is possible to walk on the reef all the way to the tip at low tide (ebb), except when the birds are breeding here. It is important to be aware of the tides, as there can be strong and dangerous currents at the reefs junction to Samsø during high tide (flow). East of Stavns Fjord, in Kattegat, lies a group of small islands (Kyholm, Lindholm, Rumpen, Vejrø) with a couple of sandbars. The entire area is to be protected.