Tunø is a Danish island in the Kattegat, approximately 4 km west of the neighbouring island of Samsø. The island covers an area of 3.52 square kilometres, has a circumference of 9.5 km (5.9 mi) and has total of 66 inhabitants as of November 2022. It comes under the administration of Odder municipality. Tunø By is the only village on the island, with the hamlet of Løkkegårde as the second most populated area.

Samsø is a Danish island in the Kattegat 15 kilometers (9.3 mi) off the Jutland Peninsula. Samsø is located in Samsø municipality. The community has 3,724 inhabitants (2017) called Samsings and is 114 km² in area. Due to its central location, the island was used during the Viking Age as a meeting place. The etymology of the island's name is unknown.