A distance obtaining unit obtains the distance between a work implement and a design terrain. A work aspect determining unit determines a work aspect by the work implement. A limit velocity deciding unit limits the velocity of the work implement when the distance between the work implement and the design terrain becomes smaller. When the work aspect is surface compaction work and the distance between the work implement and the design terrain is within a first range of at least a portion that is equal to or less than a predetermined first distance, the limit velocity deciding unit increases the limit velocity of the work implement in comparison to when the work aspect is an aspect of a work other than surface compaction, or cancels the limiting of the velocity of the work implement.