An A Song of Ice and Fire and Game of Thrones fan that goes by the handle carpiediem on the Westeros.org fansite has created an interactive map for the lands featured in the novel series and television show that includes filters for each chapter of the novels and each episode of the show. The map can also be filtered to show the paths of popular characters like Eddard Stark.
The map is based on the earlier cartography work of fans serMountainGoat and Tear, and uses an interface based on the Google Maps API to function with additional custom tiles. The map also includes a slider to indicate how far a user has read or seen so as to prevent any unintentional spoilers. As carpiediem notes, given that this is an unofficial map it may contradict official sources in some places.