If you're interested in walking, and thousands of us are, there are all manner of guides available to provide interesting routes within many of Great Britain's wilder places. Most of these are in printed form, however, and few have enough illustrations to lead you step by step.

Parallax Interactive Guides aims to get around that with its new range of CD-based guides, the first of which offers 10 circular tours of parts of North Dartmoor. Each trip is divided into 20 or more screens, breaking down the walk into manageable chunks. Each screen is heavily illustrated with well-composed photos showing key points in the route or illustrating interesting flora, fauna or archaeology. There's a lot more illustration here than in most paper-based guides.

The information doesn't stop there, though, as there are also details of pubs and cafés where you might like to eat or drink at the end of your walk, and plenty of information on campsites and equipment shops in the area. There's even a page on each of the major towns and cities in Devon.

Taking advantage of the interactive medium, each circular walk contains one spot where a complete panoramic video is included, to provide a full 360-degree view of some of Dartmoor's most spectacular sights.

The Parallax guides are the idea of Aldo Carbonari, a professional graphic artist who is also a very keen walker. The design training shows in the layout of screens within the guide, which are clear and very easy to navigate.

You can print any of the screens from the CD to take with you, but in a new offshoot to the series, you can also buy a downloadable version, with just the pictures and text for the walks, in a format suitable for an iPod Video. This is ideal, as you can view the places you should be reaching at any point in a walk, to make sure you're going the right way. There will soon be a version for Smart-phones as well.

This is the first in a series of guides that will build to cover most of the main national parks and some more exotic locations. By the end of year there should be a similar guide for walking Mt Blanc, for example, as well as Dartmoor South, the companion volume to this first product. You can sample and download one of the walks by visiting the Parallax Interactive Guides site.

To make a CD version of a guidebook more attractive than its printed counterpart, it needs to offer extras that are not available in printed media. Parallax Interactive Guides do this with panoramic videos, the ability to download to an iPod and the much larger number of illustrative photos than a typical guide book would show.