The flood of travel along the streets surrounding the block is, in the main, what determines the value of the land within the block. The larger the stream of travel, the greater the land value. This is particularly true in the business portion of the city. In residence and manufacturing districts, it is not so much the stream of travel along the streets surrounding the block as it is the short, direct connection by means of the street in front of the block with the main streams of travel along the main streets. The similarity of the streets of a city to a river system consisting of a main stream and its branches all the way back to the little brooks and rivulets is striking, and if it be borne in mind, the problem of determining land values is much simplified.