The Ice World adds to the already freezing conditions of Silent Hill. Gigantic glaciers begin to appear and freeze everything, breaking and twisting objects in their path. Certain areas are blocked by sheets of ice and the Raw Shocks make their appearance and chase Harry down.
The environment also has many instances of crashed vehicles and damage to buildings, indicating the Ice World may not just be affecting Harry. Doors and certain ledges within the Ice World are highlighted with blue edges to show the player that they can go there. As the game progresses, puzzles must be solved in order to open doors or areas that lead out of the Ice World. To Harry, the Ice World is a frightening place and seems much more similar to a nightmare than reality. For this reason, the chase sequences in the Ice World are called "Nightmares" or "Nightmare Sequences".
Harry first encounters the Ice World as he is walking through the blizzard that has engulfed the town to reach his house. Harry receives a brief phone call from Cheryl, who tells him that he has to run because he can't fight "them". Suddenly, the Ice World takes over and Harry ends up wandering into an alleyway where he is ambushed by the Raw Shocks for the first time. In later journeys through the Ice World, the ice itself freezes many of the people Harry interacts with, including Dahlia Mason and Cybil Bennett. Frozen ice figures of people appear in some areas as well, and are often related to the puzzles and messages the player must deal with. The Ice World mainly manifests when Harry gets closer to finding Cheryl, or when an important piece of information is discovered, and the Ice World will generally appear to halt his progress.
Because this Otherworld manifests from Cheryl's mind, the Ice World acts as a sort of barrier to her, or as a shield of protection from the truth. It is assumed to appear when Dr. Kaufmann is about to uncover some sort of truth about Cheryl that she is denying to Kaufmann and to herself.
The ice may represent Cheryl's desire to stop or "freeze" the session from going any further, or it may also be a metaphor for the "cold truth" Cheryl has been so heavily denying. Her desire to cease the therapy sessions translates into the dark world that appears to the manifestation of Harry in Cheryl's thoughts. When the environment shifts to the Ice World, Cheryl's manifestation of Harry is willing to face the Raw Shocks and all of the dangers all to find her, as she has conjured up the image of her father being similar to a "knight in shining armor" when, instead, the reality was very different.
- Snowflakes falling from the sky suddenly stop in mid-air. This is observed when the Ice World is encountered for the first time.
- The sky turns chaotic, a dark blue aura blankets the clouds and the clouds begin moving unnaturally fast.
- In one of the rooms during the forest Ice World, fish are seen hovering in the air, frozen in ice.
- During the forest Ice World, an airplane can be seen outside, engulfed by tree limbs.
- One of the rooms in the school Ice World is covered with formulas and equations written on the walls.
- Immediately after Harry falls down the steps in the hospital Ice World, looking back at the hospital will reveal that a train has crashed into the side of the wall above.