Land use patterns greatly influence traffic patterns and volumes.  When development is spread out (low density) and separated (isolated land uses), the number of trips made and the length of trips is higher than when development is more compact and different uses are intertwined.  For example, people living in a single-family house subdivision often must drive several miles to work, go to the grocery store or access a park.  In contrast, a person living in an environment of mixed uses can often walk, take transit or combine shorter trips.  If designed well, living in a denser, more urban environment can be attractive to many people.  Land use development patterns may be the most important influence on the amount of driving we do.  Sound land-use planning may be the most effective way of reducing the amount of traffic congestion we experience in our daily lives.