The Slums were the first area that Jak visited in Jak II; after breaking out of the Krimzon Guard Fortress in Escape from Fortress, Jak found his way in the Slums, and met Kor, who directed him to Torn and the Underground, which Jak joined.
In order to try and destroy the Underground in the Slums, the Baron cut off water to the area, but it was restored by Jak and Daxter, as a mission by Torn, who told them that it was things like that which made him quit the Krimzon Guard.
In Jak 3, the Northern Slums became New Haven while the Southern Slums remained but spilling with war from Metal Heads, KG Death Bots, and the Freedom League. Rubble surrounded the place. The fruit trays in the Southern Slums are not in Jak 3.
Some other changes to the Slums include Onin's Tent being there instead of the East Bazaar (due to it being blocked), the path to the Underground Hideout being concealed by more houses, and the entrance to the fortress being inaccessible. For the Northern Slums being replaced, Dead Town is inaccessible. From the KG War Factory, the path to the Hideout is seen and not concealed. This was a mistake by Naughty Dog.
The Slums is home to many of Haven's poorer inhabitants. It is a poor area with uneven roadways, small, cramped living areas and burning garbage cans. The area reflects the strife and poverty in Haven City under Praxis's rule, and served as home to the Underground resistance.
The Underground hideout is a small tucked away building, with the Underground logo on the door. It was Torn's home, and it is unknown if there were any other Underground controlled locations.
There were no seen Precursor Artifacts in the Slums.