The number of inhabitants of the towns and city centers have generelly increased, concurrent as the population in smaller towns has decreased. In Stockholm, the migration is very fast and here is also the most populous place, if one compares with other Sweden. In order to respond to the increasing population and the pressure they put on city spaces has Stockholm's town a town building strategy that says "build inwards". It means that one stem seals the town with spaces and business activities in central locations. The increased population in the towns and the densification of buildings leads however to an increased pressure on parks and public places.