A pocket park is an abbreviation for "vest pocket park", which is a small-scale park like a pocket attached to a vest of clothes. New York's "Paley Park" is the original “vest pocket park,” opened in 1967. In Japan, it began to implement around 1980, and has been set up as a small plaza in various places under the names such as "Machikado Teien," "Rojison," "Niwa Hiroba," and "Tsuji Hiroba." etc. In Katsushika, it is being installed under the name of "Pocket Park" in order to improve disaster prevention and living environment. This poket park was developed as part of the "Yotsugi 1-2 Chome District Dense Housing Urban Development Promotion Project" to improve the living environment for disaster prevention functions in areas with many old wooden houses. Its name "Kan Kan Hiroba" (Kan Kan plaza) comes from the nearby Kankan railroad crossing, and a real railroad crossing barrier donated by Keisei Electric Railway Co., Ltd. is set there.