Mårten Trotzigs gränd is the narrowest street in Stockholm. At its narrowest point it is only 90 cm.
Mårten Trotzigs gränd got its name from the German merchant Mårten Traubtzich who bought houses in the alley in the end of the 1600th Centuary. He became one of richest inhabitants in the city, but was attacked and murdered in 1617.