The Cult of Orcus
[From the Dungeon Master’s Guide]
Fallcrest lies near the middle of the broad borderland region known as the Nentir Vale. The vale is now mostly empty, with a handful of living villages and towns scattered over this wide area. Abandoned farmsteads, ruined manors, and broken keeps litter the countryside. Bandits, wild animals, and monsters roam freely throughout the vale, threatening anyone who fares more than few miles away from one of the surviving settlements. Travel along the roads or river is usually safe — usually. But every now and then, travelers come to bad ends between towns.
The Nentir Vale is a northern land, but it sees relatively little snow — winters are windy and bitterly cold. The Nentir River is too big to freeze except for a few weeks in the coldest part of the year. Summers are cool and mild.