Speaking of Washington, the D.C. Underground Atlas is a project to map all the tunnels under the city: utility, transportation and pedestrian tunnels alike, from metro and water tunnels to the underground corridors connecting congressional buildings. The maps are presented as Esri Story Maps and there’s lots of accompanying text. The project is the brainchild of Elliot Carter, who is profiled by CityLab and the Washington Post: both pieces reveal one challenge in mapping the underground infrastructure of Washington—getting past security concerns. [WMS]