Maps are wonderful things to have, even if you do no more with them than pull them out, ponder over them for a while, and then return them to safe storage. New releases from National Geographic's Trails Illustrated division give you more reason to dream about exploring the National Park System.

While more and more mapping information is available for GPS units and smart phones, I still like the option of unfolding a map, laying it flat on a table or tent floor, and tracing my finger along the day's route. And the Trails Illustrated maps are, short of an up-to-date 7.5-minute USGS topographical map, among the best resources you can take into the field. Waterproof and tear-resistant, these maps not only trace hiking trails through the parks but point to backcountry campsites, lean-tos, prominent features such as waterfalls, and front-country features such as campgrounds, visitor centers, and even gates that you might encounter.

New to this series is a map that takes a closer look at one section of Great Smoky Mountains National Park, and one devoted to Voyageurs National Park.

Map 317 (MSRP $9.95) focuses on the Clingmans Dome and Cataloochee areas of Great Smoky. While its 1:40,000 scale isn't quite as refined as the USGS's 1:24,000 standard, it is better than the 1:70,000 scale of Map 229 that covers the entire park.

Among the additions on the new map is formal designation of the Mountains-to-Sea Trail (the trail was on Map 229, but not designated as the MTS trail) that descends the park's eastern flanks below Mount Collins and runs all the way to the Atlantic and Cape Hatteras National Seashore; additional points of interest along Newfound Gap Road, such as the Old Deep Creek and Swinging Bridge quiet walkways; the addition of the Ferguson Cabin Trail and Science Center Trail along the Cataloochee Divide; and just better overall detail thanks to the better scaling.

If you're planning a hiking visit to either of these areas of Great Smoky, the new map is worth the investment.

Map 264 (MSRP $11.95) covers Voyageurs National Park in a 1:50,000 scale, so you won't find as much detail as you could obtain in a USGS topo. Still, for a decent overview of the park, one that shows cross-country ski and snowmobile trails, houseboat mooring sites, backcountry campsites, and portages, this should meet your needs. For winter users, the map also shows where you might encounter thin ice.

As with other Trails Illustrated maps, both of these maps provides basic park information, safety information, contact information, and reservation and permitting information.

Now, there are some improvements Trails Illustrated perhaps should consider with some of its maps. In studying the Shenandoah National Park map (Map 228), which was last revised in 2007, I was disappointed to find that the cartographers did not include mileage information between points along the park's trails. The reason, I was told, is that "there are some discrepancies regarding the mileages." And while the map currently is going through another revision, there apparently are no plans to try to resolve these discrepancies, and so users will continue to have to guesstimate distances.

Additionally, it'd be nice if the orientation of these maps was a little more user-friendly when it comes to flipping the map over. For instance, the Shenandoah map features the northern end of the park on one side, and the southern end on the opposite. If you're tracing the route of the Appalachian Trail, for example, south through the park and reach the bottom of the northern section, you need to both flip the map over and rotate it 180 degrees to continue. It would seem to be easier if you simply could fold the bottom of the map up and find yourself at the top of the southern section, no?

That said, I still like these maps for getting the feel of a park and negotiating its backcountry. Continued fragmentation of parks into a series of maps, as was done with Great Smoky, is a move in the right direction.