The wide variety of visualization methods for numerical values have, up until now, outweighed the relatively modest selection available for nominal dimensions. Theme Landscape is a visualization application designed for tagged data that typically contains a large number of nominal dimensions. It provides an overview of large data volumes, doing so by positioning objects in a landscape according to how similar their tags are. HexBoard technology has been used for dimension reduction. A further distinctive feature of Theme Landscape concerns the icons. The tags that belong to an object can be identified according to the shape of its icon. Each keyword is assigned to its own unique glyph and these glyphs form, in any combination, a hexagonal icon. For the prototype a data archive of interactive media artworks has been used, which had been tagged using a taxonomy.