The island is part of Esbjerg Municipality and is situated approximately 12 kilometres (7 miles) southwest of the ancient town of Ribe.
Mandø is barely accessible by road at high tide over an unpaved surface level causeway of about four kilometers in length that connects the island to the mainland.
Extensive mudflats and tidal marshes encircle the island and provide breeding areas to multitudes of birds and other organisms.
[3] In the past centuries several large earthen dikes have been constructed around the perimeter of the island, although substantially set back from the shoreline.
Conventional motor vehicles can access Mandø Island via a causeway, an unpaved roadway, although this route is compromised in storms at high tide.
Alternatively many visitors reach the island by way of a specially designed tractor-pulled bus with greatly oversized tires.
Mandø is located midway between the two larger islands Fanø and Rømø which are connected to the mainland by a ferry and a road running across a causeway, respectively.
The principal ecosystems on this island are: tidal marsh; mudflat; littoral zone; and upland grassland.
Mudflats and marshes afford birds a safe and undisturbed location for feeding, resting and breeding.
[7] but it is believed people lived there before then, with archaeological remains of Gammel Mandø village, located close to the mainland causeway.
Residents often experienced that an early autumn storm surge washed away the entire hay harvest.
[15] On 18 June 2010, a tractor-drawn tourist vehicle overturned in a one meter wide, 50 cm deep hole in the Wadden Sea between Mandø and Koresand.
It appears from one research study that conflicts exist among the residents, tourists, and some departed islanders who retain holiday homes.
1974) entitled Mandø was published in 2009, and describes the petty intrigues and struggles of a group of friends holidaying on the island, with reference to the mudflats and sea level rise.
[17] A 2023 movie produced by Elk Films, As the Tide Comes In (Før stormen, 1h 28m) by Juan Palacios and Sofie Husum Johannesen shows the struggles of the remaining 27 islanders, focussing on the oldest and the youngest (in his 40s), with rising sea levels as a storm surge advances.
[9][18] One review says "Impressively, the film walks that delicate line of both celebrating Mando as an entirely unique place, an island lost in time, and holding it up as a King Canute-esque symbol for humanity’s ongoing fight to hold back the tide.