Järnvägsbron Årsta-Älvsjö, Railway bridge in southern Stockholm, Sweden

Älvsjöbågen is a single-track railway bridge that runs 1,396 metres in a curve between Västberga and Årstaberg in southern Stockholm, reaching about 14 metres above the ground. Its deck was cast in 38 stages using a 70-metre formwork carriage that moved forward as each section set, a method rare in Sweden. The bridge carries northbound long-distance, regional and freight trains into the Citybanan tunnel.

The project began in the early 2010s and was completed by the middle of the decade to handle growing demand in Stockholm's rail network. The new bridge significantly improved train connections in the southern region.

The name was chosen in a 2015 competition run by P4 Stockholm at Trafikverket's initiative: over 1,500 suggestions came in, including Ryggraden and Årstafrun, and Älvsjöbågen won with 1,479 of 3,201 votes. The bridge carries northbound long-distance, regional and freight trains, while the older Årstabron handles southbound traffic.

The bridge is part of Stockholm's rail network and can best be viewed from the nearby stations where trains regularly arrive and depart. Visitors can see the structure from the valley floor or from paths along its edges.

The bridge deck was cast in 38 stages using a 70-metre movable formwork carriage, a method rare in Sweden and otherwise mainly used in Asia and the rest of Europe. The name came from a P4 Stockholm competition in 2015, where Älvsjöbågen won with 1,479 of 3,201 votes.