The Jätkäsaari area is comprised of four previous islands now adjoined to the continent: Hietasaari, Saukko, Saukonkari and Jätkäsaari. The islands have been inhabited from the 19th century. In addition to permanent residents, the people of Helsinki had summer villas on the islands. Boat trips were made to them, and the sand beaches attracted swimmers. People swam on Saukko during the summer and went there sledding in the winter. The rocks of the island were high and magnificent – even too fierce for the smallest ones.
Legends say that Uno Kurtén, CEO of the life insurance company Kaleva, lived on the island during summers and had himself rowed to the island every single summer evening after a day at work.
The islands were occupied by industry, such as candle and tar plants, in the early 20th century. The rocks of Saukko island were quarried and their red granite can be seen on the walls of many Helsinki monuments: the Uspenski Cathedral, St. John's Church and Pitkäsilta Bridge.
Construction work on the harbour began in 1913. So much seafloor was filled that the area tripled from the original plans. The four islands in the area – including the Saukko island – were adjoined to the mainland. The area was given the name Jätkäsaari in 1928. According to one view, the area was named Jätkäsaari, Finnish for "Stevedore Island," after the stevedores that worked in the area.
The harbour served Finnish industry for over 80 years. In 2008, the cargo ship harbour was relocated to Vuosaari, and the reconstruction of Jätkäsaari as part of Central Helsinki began. Storehouses designed by Lars Sonck, Huutokonttori that used to provide employee facilities for the port, and the massive 1970s Bunkkeri warehouse are reminders of the past.