Every child should probably have visited a playground while growing up, and when I was a child, playgrounds still held sand, as seen here (albeit covered with dead leaves).
Playgrounds then resembled little forts in the middle of a sand island, and we played all sorts of games, from catching, freeze and melt, to 'Defend the Keep' sort of games. Having a sand pit downstairs meant not having to go to beaches that are usually too far away from home to visit regularly. Playing with marbles and building sandcastles were alternative options once we became tired from the running around.
These days, playgrounds are fitted with rubber surfacing and come with specially designed equipment that are deemed safer and have educational value. Yet, these new designs seem to inhibit the very purpose playgrounds were originally made for - proper play time.