The German wine-growing region of Franconia used to be divided into the three areas of Maindreieck, Mainviereck and Steigerwald with 23 Großlagen and 216 Einzellagen. In November 2011, the members of the Franconian Winegrowers' Association decided on a new arrangement. The three old areas will be replaced by 12 much smaller ones. These will also replace the 23 large vineyards in the medium to long term. The old areas once played a role in the predominant marketing of Franconian table wine, but they had lost that role for some time. Before this conversion, the following description applied to the Mainviereck area:
The very small Mainviereck area is located in the west and covers only about 330 hectares of vineyards. It is named after the landscape formed by the curved course of the Main in the form of a quadrilateral open to the north with the municipalities of Gemünden, Wertheim, Miltenberg and Aschaffenburg forming the corners. Primary rock soils with mica slate, quartzite and gneiss predominate here. The most common varieties are Müller-Thurgau, Riesling, Silvaner and Bacchus. The area is divided into two large vineyards, Heiligenthal and Reuschberg.