The GeoMashup CodeCamp is an intensive course arranged at the University of Helsinki, Department of Computer Science during the autumn lecture break of 2011 (Friday 21st to Monday 31st October). During CodeCamp courses the students work together to develop of small-scale applications in small groups. This time the goal of the course is to build together mashup-style applications taking in geospatial (location based) data from at least two different sources, and visualizing it into useful, interactive web applications.