The links above lead to a collections of photographs and some commentary about some of the "wild" places of Wales and England visited during the fall and early winter of 2001 while I was teaching in the Study in England Programme in Birmingham. Except for the Stiperstones and the Coniston area of the Lake District National Park, all of these are easily accessible from Brum by train and/or bus--good walking starts a kilometer or less from where you get off train or bus (note that weekend schedules for buses and trains can vary considerably from the week-day schedules--especially in Wales, in parts of which there may not be any bus service at all on Sundays!).
England and Wales are noted for their castles and cathedrals and other ancient structures, their gardens and hedges and pubs, and for the beauty of their agricultural countrysides. There isn't much really wild country in either--nothing on the order of parts of the Amazon Basin or Andean mountain ranges, or Alaska's Brooks Range, or even the Bob Marshall Wilderness, or the Boundary Waters Canoe Area Wilderness. Much of the British countryside has long since been stripped of its "natural" cover--and kept that way through farming, mining, logging and sheep grazing. Nevertheless there are beautiful areas of relatively wild country, some of which are pictured herein. And remember, if the fog and haze aren't already in the way, the fewer the trees, the better the views!
An important thing to note is that there is very little public land in England and Wales. Even the National Parks consist mainly of privately-owned land. Fortunately, there is a "right to roam" in force which permits you to wander over vast stretches of private land ... provided that you stay on the defined rights of way. Since these rights of way (along trails) are often not well marked, you will need maps and guidebooks to do this. Many owners of land are unhappy about your right to cross their property. To avoid worsening the situation stay on the paths to which you have access rights. Do not climb over or through fences, walls or hedges. Make your way through them only where passage is clearly given by a gate or stile.
Another thing about England and Wales: even after a couple of hours of tough walking beyond the end of the nearest road or rail line, you are likely to encounter a lot of other people who are also out to enjoy nature--far more than you would likely be to meet in the US under the same walking conditions. A lot of Brits do a lot of country walking and hiking ("rambling" they call it). You would have to work pretty hard to avoid people. So enjoy them! Most Brits on the trails share some of your interests and are quite friendly (if you are!). And they provide a helpful margin of safety if you should seriously injure yourself. And you can get into trouble in the wilds of England and Wales. Breaking bones, spraining ankles, and getting hypothermic (even in summer, what with all the wind and rain which may be enountered) are possibilities year round. Remember, some of the world's great mountaineers have cut their teeth (and arms, and legs, and heads and hands!) on the cliffs and mountains of England and Wales.
MAPS: High quality maps and guidebooks are easily available in England and Wales, even in small towns. In Brum, Waterstones on the University of Birmingham campus and in the city center (and they are not the only source) have quite complete collections of topographic maps and walking guidebooks covering all of Britain.
Multimap.com makes available excellent topographic maps (1:25,000 and 1:50,000) on the web--click here if in Britain, here if in the U.S. On several of the walking areas presented in this web-site (e.g. Carneddau (/Snowdonia N.P.) I have included a link to one of their maps. Note that in the box to the left of the multimap page you can change the scale and move the area covered to north, south, east or west.