The World's Smallest Park

From Wikipedia:

"Mill Ends Park in Portland, Oregon, United States, is a small park that was created on St. Patrick's Day, 1948, to be a colony for leprechauns and a location for snail races. It is the smallest park in the world, according to the Guinness Book of Records, which first granted it this recognition in 1971.

The small circle has featured many unusual items through the decades, including a swimming pool for butterflies (complete with diving board), a horseshoe, a fragment of the Journal building and a miniature Ferris wheel (which was delivered by a regular-sized crane)."