Wizards of the Coast has several free adventures on their website that take place in the wilderness.
Here's a link to the adventure archive:
http://www.wizards.com/default.asp?x=dnd/oa/20030530b&page=1
Desert Sands - It's time to heat things up in your campaign with this
desert miniadventure. Merchant caravans have been disappearing as they cross the sands. Who or what is responsible and, most importantly, why is it happening? The PCs can make strange alliances or deadly enemies as they seek out answers to these questions.
Environmental Impact - [font=Arial, Helvetica, sans-serif]
A mad druid named Drylle holds a grudge against the forest village of Sumpter, which he views as an unlawful encroachment of civilization upon wild lands. In an effort to drive the villagers away, he has brought unseasonably hot and rainy weather to the area. [/font]
Fang, Beak, and Claw -
Fang, Beak, and Claw involves an evil druid of Malar, his cronies, and a tamed owlbear. Living in a sheltered grove altered by the druid's spells, they are using the beast to harass loggers in the
woods and help in their cruel hunts.
House of Harpies - A new mini-module by Owen K.C. Stephens challenges PCs with an invigorating adventure. It's not often that a theives' guild needs help. Drop this free online adventure into your campaign in
any wilderness setting or just outside any city.
Ill Wind in Friezford - A new mini-module by Skip and Penny Williams challenges PCs with a haunting adventure. What is the wild hunt? Will the PCs survive their visit to Friezford? Drop this free online adventure into your campaign in
any wilderness setting that contains a former trading route.
Into the Frozen Waste - A druid in a small frontier town at the edge of the
tundra is gathering stalwart companions for a trading venture across the ice. Only the bravest need apply, he says, for survival in this harsh environment is not easy. But is there more to his venture than he lets on? What's a druid doing in the trading business? Who is his mysterious sorcerer client?
One Last Riddle - When the great sphinx Ujaset is slain, his ghost offers treasure to any heroes brave enough to avenge his death. Can your party solve his
One Last Riddle to discover and defeat his killers?
[desert]
Road to Oblivion - [font=Arial, Helvetica, sans-serif]
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?[/font]
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Shoals of Intrigue - [font=Arial, Helvetica, sans-serif]Spies are common in the coastal cities, and the overlords depend on them to gain information about one another's plans. One such spy has gained vital information that could prevent a war and stabilize the entire coastal region, but his ship was lost at sea before he could deliver his message. Was it an accident, or could some evil force have an interest in preventing his information from reaching its destination? It's up to the intrepid PCs to find out! Drop this free online adventure by Robert Wiese into a coastal area of your campaign world. [/font][/font]