How long did it take to build the iss?

The construction of the International Space Station (ISS) began in 1998 and continued over several years, with the first module, Zarya, launched in November of that year. The assembly involved numerous missions and additional modules, culminating in the completion of its core structure in 2011. However, the ISS remains a work in progress, with ongoing upgrades and maintenance, making its construction timeline span over two decades.