Smugglers' Notch State Park is a Vermont state park near Stowe in Lamoille County, Vermont. It is named for a split between Mount Mansfield, the highest peak of the Green Mountains from Spruce Peak and the Sterling Range.
Stewie heads to Smuggler's Notch State Park to scatter Rupert's ashes from the peak of Mount Mansfield after he is destroyed by Brian in "Dog Bites Bear". Brian tags along to keep an eye on Stewie but his very presence irritates him to the point they start fighting, which leads Brian to reveal that his destruction of Rupert wasn't an accident. This infuriates Stewie but their fight ends with him falling down the side of a cliff and twisting his ankle to the point he could not walk. Brian builds a litter to cart him along to the top of the mountain where they open up their feelings, as Stewie's constant attention to Rupert annoys Brian while he in turn is concerned about Brian's advanced age taking him away in the not-so-distant future. They reach the summit and scatter his ashes, and are able to bond again after doing so.