From Publisher's website:
Oblivion is a town like no other. Situated in a hidden valley within a high mountain range and accessible only via air or a secret tunnel through the mountains, it has remained unknown to all except its inhabitants for uncounted centuries. What happens when a natural disaster exposes the town to the world and lets loose an ancient danger at the same time? Will the PCs aid those in need? Road to Oblivion is a D&D adventure for four 11th-level PCs, and it was designed by Penny Williams!
Beginning the Adventure
The adventure begins when the heroes arrive at the site of the avalanche. Mountain View is a few miles to the east of the blockage, and Oring is to the west and down the slope.
1. Avalanche Site
Read or paraphrase the following when the characters reach the point where the rubble blocks the Oring Road.
The Oring Road serves as the sole connecting highway between the thriving town of Oring in the foothills of the mountains and the smaller towns that cling to the slopes to the east. For the most part, it seems reasonably well maintained. But as you round a bend, the road disappears under an immense heap of rubble and loose earth. It looks like an avalanche has recently decapitated the mountain here, burying the road and the lower slope deep under earth and stone. The rubble extends all the way up the slope to the now-ruined mountaintop and for as far as the eye can see downward. Measured from the roadbed, the pile looks to be about 50 feet tall.
If the characters are approaching from the west, continue with the following.
Just before the edge of the rubble heap, a second road joins this one. It leads off to the right, over the new, lower top portion of the mountain. It looks little used but passable. At the juncture of the two roads is a small sign with an arrow pointing down the secondary road. It reads, "Oblivion."
The sign was placed here by the pixies as a joke when they realized that the former access tunnel for the valley was now an exposed road. They have not yet mentioned this situation to the lillends or the inhabitants of Oblivion.