The Center for Geospatial Information Science hosted and helped to organize a number of events for GIS Day this year.  The day kicked off with a morning OpenStreetMap Mapathon in the McKeldin Library.  The American Red Cross / Missing Maps team were on hand to introduce the mapathon and provide support for new mappers.  A Lightning Talk session was held over lunch in the Center with 13 speakers from across campus presenting on a range of topics in bite-sized, 3 minute, talks.  In the afternoon, GIS Day participants attended the Project Sidewalk mapathon, gaining hands-on experience with mapping accessibility in Washington DC.  All-in-all, a successful GIS Day at the University of Maryland.