Gassy is a village in the administrative district of Gmina Konstancin-Jeziorna, within Piaseczno County, Masovian Voivodeship, in east-central Poland. It lies approximately 6 km east of Konstancin-Jeziorna, 13 km east of Piaseczno, and 21 km south-east of Warsaw. In 2014 ferry to Karczew started service. According to people working on this project the main problem was official "no-entry" car, despite road there. Without cars it was not economically reasonable, and after this problem was solved by removing the rule, the ferry started.