This paper introduces the notion of map-based wiki, a wiki that allows users to interact with each other and with information through a digital map. The map, either geographic or conceptual, becomes a medium for creating knowledge through digital annotations. Annotations may be multimodal. Audio or icon notes set the mood for perceiving map space, while text or graphic notes create information space. We analyze examples to gauge mapbased wikis' potential, then focus on Banco Territorio, a map-based wiki designed for information and emotional spaces, which localizes both spaces to overcome cultural misunderstanding in social interaction through digital maps.