The ferry for Baltrum departs from the small port near the village of Neßmersiel (in the parish of Dornum) with connection to the train station of Norden.

It covers an area of 6.5 square kilometres (2.5 sq mi) and has a population of around 600 people, swelling to about 3,500 during the summer months due to tourism.

The highest point on the island is a central coastal dune with a viewing platform on top called Aussichtsdüne in German and is 19.3 metres (63 ft) above sea-level.

In 1398, the island was mentioned for the first time in a document of enfeoffment as Balteringe meaning either "pasture" or "[the place of] the sons or followers of Balter" in Old Frisian.

The geographers Strabo and Pliny the Elder provide an indication that the island existed since the first century BC and AD.

In 1398 Baltrum was mentioned in a document for the first time, when Widzel tom Brok assigned Balteringe (besides the other islands) to Duke Albert I of Bavaria and received them back as fief.

Besides the approximately 500 inhabitants about 3,000 guests are constantly living on the island during the peak seasons exhausting the acceptance capacity of the two small villages.

The only exceptions are vehicles of the volunteer fire department, an ambulance, a few wheel loaders and some machines needed for the coastal protection.

There are no street names on Baltrum, and postal addresses are related to the chronology of the development of the areas meaning that the numbering is geographically independent.

The port of Neßmersiel was inaugurated in 1970 and extended by a cargo wharf with 35 metres (115 ft) in length from April to August 2008 due to the relocation of the freight transportation.

At the event of low water Baltrum is reachable from the port of Neßmersiel as a guided walk across the mudflats taking 2.5 hours.