Some more pictures that can be used as adventure settings. These were taken at Lost River Gorge & Boulder Caves in North Woodstock, New Hampshire. It is a 3/4 mile hike down and then up a gorge. Along the way up are various side caves you can enter. You should be able to click on the pictures for a larger view.
These are of the walkways outside the caves. These could be the scene of trails through some woodlands or even perhaps an elven habitation.