1. A method in a computer system, the computer system comprising a database, for determining a predicted amount of time required to travel from one location to another, the method comprising: maintaining an indexed lookup table, in the database, that includes approximate travel times associated with traveling from within selected departure grid portions to within selected destination grid portions, each selected departure grid portion and each selected destination grid portion being associated with at least one address of interest in a region, the grid portion derived to represent geographical regions whose traversal time relates to a predetermined amount of time wherein the grid portions represented in the indexed lookup table have been sized so that each grid portion is expected to have a traversal time based on a predetermined amount of time, the address representative of a physical location within the geographical region; updating the travel times with historical data that includes actual amounts of time that have been required to travel from selected departure grid portions to selected destination grid portions; and searching the indexed lookup table to predict an approximate travel time from a first location to a second location.