In 1622, the prefix Söder 'south' was added to distinguish from the then recently founded town of Norrtälje, located 110 km northeast of the city.

The Western Main Line for trains between the east and west coast of Sweden opened in 1862, with a station in the city.

The sale of pretzels, among other aspects of the resort town, was described in the magazine Svenska Familj-Journalen (English: Swedish Family Journal) in 1881.

The reason that the area would subsequently expand (mainly in a southerly direction) is largely due to the fact that the Central Railway Station was placed near the city park.

The older wooden houses that previously existed in the central parts have largely been moved up to Torekällberget, which is Södertälje's open-air city museum.

When Marenplan served as city port, ships carrying goods would moor there, and sell their merchandise to individuals and traders waiting at the quay.

The importance of Olof Palmes plats was especially high when it served as hub for the city buses, which have since been moved to the Central Railway Station.

[7] The largest are Kringlan (architect Erik and Tore Ahlsén), Luna, Åhléns and Telgehuset (which initially was a Domus department store).

A notable exception to the otherwise modern structures is Skandinaviska Enskilda Bankens bank palace, which was built between 1901 and 1902 at the initiative of the tobacco trader TH.

The area where the secondary school moved is east of the canal, the Museum of Biology and the present day city hospital.

As the land post-glacial rebound made Södertälje Canal shallower, it became increasingly difficult for merchants to get between Lake Mälaren and the Baltic Sea to sell their goods.

Across the square lies the current Södertälje District Court, which was designed by Åke Lindqvist, and built by Anders Diös.

Around the engraving, which is located in close proximity to the road, have today been cleaned up and put up signs from the Swedish National Heritage Board with translations of the inscription.

Until the early 2000s, the only really large collection of shops, apart from local neighbourhood centres, was Weda in the eastern part of the city.

[citation needed] Many were willing to pay to avoid having to walk to the swing bridge and back again if they lived around the areas of Tältet or Hagaberg.

In September 2003, a referendum among the residents of Södertälje Municipality was held, where they could decide if they wanted a new car bridge to be commissioned at the site.

On 13 February 2016, all four members of the English rock band Viola Beach (along with their manager Craig Tarry) were killed during their first overseas tour when their car fell from a bridge in Södertälje.

[30] The Swedish Police Authority opened an inquiry and found that Tarry, who was driving, had no traces of alcohol nor drugs in his blood.

[31][32] They also found that Tarry had engaged the brakes before reaching the bridge, ruling out the possibility that he had fallen asleep, and authorities said the incident ultimately remained "completely inexplicable".

International trains to cities like Oslo and Copenhagen call in Södertälje, in addition to local, regional and national services.

The many railways that pass through Södertälje mean that it is possible to travel to Sweden's three major cities (Stockholm, Gothenburg and Malmö) without changing trains.

Retail shopping outside the city centre is mainly located in Moraberg on the eastern side of the canal, as well as Vasa Handelsplats in the western part.

In 2018, KTH moved in to a newly built campus in Södertälje Science Park drawn by the architect firm White.

Both individual courses and whole university programmes are offered within a variety of subjects, meaning students can study at the campus all the way until graduation.

The general introductory course for students pursuing a career within the Church of Sweden, as well as Allmän kurs, which is mostly non-religious and supplements normal secondary school education.

The property was purchased by Lars Johan Hierta in 1863 to serve as a summer house for Wendela, her daughter Signe and the jointly unrecognised son Edvard Faustman.

After being acquired by Södertälje Municipality it was moved to its present location between the canal and Marenplan in the city centre, and underwent extensive renovations.

[106] In 2015, Grafikens Hus (English: House of Graphics) decided to relocate to the city from nearby Mariefred, meaning there would be two art museums in Södertälje.

[citation needed] There is an indoor swimming arena in which elite training and races are held, named Sydpoolen (English: the South pool).

Södertälje, and the rest of Stockholm region has a humid continental climate (Köppen Dfb) and displays four distinct seasons.