Trångsund (Swedish: "Narrow Strait") is a small street or alley in Gamla stan, the old town of Stockholm, Sweden. Stretching from Stortorget in front of Storkyrkan to Storkyrkobrinken, it is intercepted by Ankargränd and Spektens Gränd and forms a parallel street to Prästgatan and Källargränd.
In the 15th century the name Trångsund was used for a narrow street in the southern end of Gamla stan, possibly Mårten Trotzigs Gränd, but by the end of the 16th century it was used for the formerly nameless alley. As the church used to be surrounded by a graveyard, Trångsund used to be much narrower before both the graveyard and the wall around it were demolished in 1816.[1]