What is the length of the ISS's integrated truss structure in meters?

The ISS’s integrated truss structure is 109 meters long, rounded from its measured length of 108.5 meters.

The Integrated Truss Structure is the station’s long external backbone. It supports the large solar arrays, thermal-control radiators, communications equipment, external payloads and the rails used by the Mobile Transporter. Although it is not a pressurized living area, it carries much of the infrastructure that allows the laboratories and habitation modules to function.

The truss was assembled in orbit in stages, largely during space-shuttle missions, from 2000 through 2009. It consists of 11 main segments plus the separate Z1 truss. The segment names use positional letters: P means port, S means starboard and Z means zenith.

The 109-meter figure can be confused with other ISS dimensions. NASA also gives the station’s overall structure as about 109 meters across its extended arrays, while its module length is about 51 meters. The truss’s 108.5-meter measurement is commonly rounded to 109 meters in quiz references.