Offenbach am Main is a city in Hesse, Germany, on the left bank of the river Main. It borders Frankfurt and is part of the Frankfurt urban area and the larger Frankfurt Rhein-Main urban area. It has a population of 138,335 (December 2018).

In the 20th century, the city's economy was built on machine-building, leather-making, typography and design, and the automobile and pharmaceutical industries.

The inner city area of Offenbach is quite large and consists of the historic center of the city and its expansions of the 1800s. Three formerly independent suburbs were incorporated in the first half of the 20th century: Bürgel being the first in 1908, then Bieber and Rumpenheim in 1938 and 1942.

South of the inner city area are the suburbs Lauterborn, Rosenhöhe and Tempelsee. Kaiserlei is a commercial district in the far west of the city bordering Frankfurt. In the west Waldheim is a residential neighborhood on the city limits with Mühlheim am Main. In 2010 the eastern part of the city center was officially named Mathildenviertel, as the area was already unofficially called by the locals.

Unlike most larger cities in Germany, Offenbach was not completely divided into districts. Only the nine neighborhoods mentioned above were officially districts, leaving the largest parts of the city officially unnamed. Although specific names for neighborhoods and areas were already in use among the locals and residents.

In June 2019 the city council approved a new act that subdivides the city's area entirely into 21 districts. The nine existing districts largely remained the same, most of them were even expanded. The new districts were laid out after the already by locals commonly known neighborhoods, such as the Westend, the Nordend or Buchhügel. A completely new name was only needed to be found for one neighborhood south of the city center, which never had commonly used name before: Lindenfeld. The name derived from an old name of a land lot in this area, when it was still fields in agricultural use prior to the 1800s.

In Offenbach there is no specific Old Town, but there are several buildings which survived bombing during the war and have been restored. One of them is the Neo-baroque palace Büsingpalais with the Büsingpark, reconstructed in the 1980s. Today it is used as a congress center close to the Sheraton hotel. Between the shopping area and the Main, is the Lilipark and the Lilitemple, named after Johann Wolfgang von Goethe's fiancée Lili Schönemann. The most important building is the Isenburger Schloss [de] (Isenburg Palace), a renaissance palace from 1576. It is today used by the Offenbach Design University which is next to it. There is also a neoclassic palace in the borough Rumpenheim, the Rumpenheimer Schloss it now serves exclusively as domestic dwellings but the park is public.

• Isenburger Schloss, a Renaissance building, now used by the Offenbach Design University
• Büsingpalais with Büsingpark
• Wilhelmsplatz a square with coffee houses and three times a week a market.
• Buildings of the French Protestant Church and the French Protestant Community.
• Rumpenheim Palace.
• Former Synagogue "Capitol" (now a concert hall next to the new Synagogue).
• The Westend Quarter (19th century).
• Several art deco apartment houses.
• Buildings by early 20th century architect Hugo Eberhardt: "Heyne" Factory, main building of the Design University, AOK Insurance building.
• Prefabricated houses by Egon Eiermann in Lauterborn