The 14 m2 house created by Jakub Szczęsny for Etgara Keret measures 122 cm in its widest and 72 cm in its narrowest point, what makes it the narrowest building in the world. It contains two floors with a bedroom, kitchen and bathroom. It officially opened on the 27th of October 2012 at the corner of ul. Chłodna and ul. Żelazna in Warsaw.