Portland is the town where Harry Mason lives after the events in the original Silent Hill.  Considering how Silent Hill is located in the state of Maine, it is very likely that this town is Portland, Maine, which is also Stephen King's hometown. It is also possible that the town could be a reference to Portland, Oregon, deemed one of the most haunted places in the United States.
Harry and his daughter, Heather Mason, had settled in Portland until they were found and attacked by a member of the Order (five years after Silent Hill), whom Harry killed in self defense. They then moved to a nameless town which served as the setting for the first half of Silent Hill 3.
|Eric - Tina - Bill - Jessie - Ryan - George - Emilie Anderson - Frank Anderson - Michelle Anderson|
Hanna - Lorraine - Captain - Scott Fairbanks - Greys
|Creeper - Double Head - Greedy Worm - Gum Head - Hummer - Insane Cancer - Mama - Numb Body - Nurse - Phantom - Pyramid Head - Robbie the Rabbit - Scraper - Split Worm - Toadstool - Tremer - Tuberculosis|
|Brookhaven Hospital - Central Square Shopping Center - Jacks Inn - Labyrinth - Lakeside Amusement Park - Silent Hill Historical Society - Spiral Staircase - Toluca Lake - Toluca Prison|
|Flashlight - Fog World - Little Baroness - Monster - Otherworld - Radio - Real World - Siren - Welcome Sign|
|Heather Mason - Christopher Da Silva - Vincent Cooper - Claudia Wolf - Leonard Wolf - Dark Alessa - Douglas Cartland - Alessa Gillespie|
|Rose Da Silva - Dahlia Gillespie - Suki - Travis Grady - Order Soldier - Detective Santini - Mannequin Girl|
|Armless Man - Delusion - Leonard Wolf - Lobotomy - Mannequin Monster - Memory of Alessa - Missionary - Nurse - Pyramid Head - Valtiel|
|All Hallows High School - Brookhaven Asylum - Central Square Shopping Center - Jacks Inn - Sanctuary - Silent Hill, West Virginia - Lakeside Amusement Park|
|The Brethren - Halo of the Sun - Monster - Manifestation - Otherworld - Fog World - Real World - Robbie the Rabbit - Seal of Metatron - Siren - The Order - Great Knife - Welcome Sign|