Needle, thread and knot, Modern sculpture in Piazzale Cadorna, Milan, Italy

Needle, Thread and Knot is a two-part sculpture by Claes Oldenburg and Coosje van Bruggen: a stainless-steel needle with red, green and yellow thread stands on the pavement in front of Cadorna station, while the thread reappears as a knot in a fountain in the middle of Piazzale Cadorna. The needle is about 18 metres high and the whole work nearly 86 metres long.

The City of Milan commissioned the work as part of the renovation of Cadorna station and the square in front of it in the late 1990s. The sculpture, almost 86 metres long and 18 metres high, was inaugurated in 1999; the English Wikipedia gives February 2000. In 2012 the City announced its restoration.

The three thread colours red, green and yellow were chosen by the artists to match the three Milan Metro lines existing at the time, before the M4 and M5 lines were planned. The work also paraphrases the "biscione", the serpent on Milan's coat of arms, as Gae Aulenti noted in a lecture at the Politecnico di Milano.

The work has two parts: the needle stands on the footpath in front of the Cadorna station, while the knot sits in a fountain in the middle of the square, so you walk between them. The square is a hub for the Milan Nord Cadorna railway station and the Cadorna metro stop.

The needle stands on the pavement in front of the station while the knot sits in a fountain in the middle of the square, so the thread disappears underground between them. The artists intended this split as a train entering a tunnel. The three thread colours match the Milan Metro lines existing when the work was made, before the M4 and M5 lines were planned.