"A park ranger in your PC," promises Maptech, and this elegant new CD-ROM delivers. Pick a park from the 54 offered, and you get crisp images of topographic maps; zoom in for just about as much detail as you could possibly want, short of seeing individual trees.

A nifty distance-measuring tool not only calculates the horizontal span between any two points you specify but also displays the vertical profile that is so crucial to hikers. A "line-of-sight" feature shows what you'll be able to see from that rugged peak you're planning to scale or from the parking lot of the visitors' center. The CD also contains complete brochure-like background on flora and fauna, geology and history. Of more practical value are the listings of campsites, lodging, trails, restaurants and other services. Navigating through this CD guide is a breeze-no compass required.