1. A method for a computing system to determine location-related information for points of interest, the method comprising: obtaining map information for a geographic area of interest; determining polygon-based information for the geographic area that represents actual travel distances in the geographic area by, decomposing the geographic area into a plurality of smaller areas based at least in part on the obtained map information, the smaller areas represented with a first polygon layer that includes a plurality of non-overlapping adjacent polygons of substantially similar size, and determining an associated approximate actual travel distance in the geographic area that the polygons of the first polygon layer each represent based on an average diameter of the polygons of the first polygon layer; and automatically generating a hierarchy of polygon layers that includes the first polygon layer as a lowest level of the hierarchy and that includes one or more additional polygon layers for the geographic area that are successively higher in the hierarchy, each of the additional polygon layers including successively larger polygons that each include multiple polygons from a next lower polygon layer in the hierarchy, and associating an approximate actual travel distance with each of the polygons of the additional polygon layers based on the approximate actual travel distances of at least some of the multiple polygons from the next lower polygon layer that are included in the polygon; and for each of multiple search requests for points of interest in the geographic area that are within an indicated distance from an indicated origination point, automatically using the hierarchy of polygon layers to identify a search area for the search request that approximates a subset of the geographic area within the indicated distance of the indicated origination point, the identified search area being one or more polygons from at least one of the polygon layers of the hierarchy that are selected based at least in part on the approximate actual travel distances associated with the selected one or more polygons; and providing search results for the search request by identifying points of interest that are present in the one or more selected polygons.