Online maps are a dime a dozen. You can go to Mapquest or Google Maps or Yahoo Maps and get pretty good maps of most of the United States. Some of them have driving directions. Some have satellite photos. The interfaces are all intuitive and easy. If that’s not good enough, you can get Google Earth and do maps on steroids. There’s no reason to use anything else.

But the National Atlas is still worth a visit. This site is a service of the U. S. Department of the Interior. On the surface, it’s just a regular map of the United States. The interface is a little clunky compared with some of the other online maps. But the cool part is in the layers. In addition to the usual demographic layers (political boundaries, highways, city names, etc.), there are lot of other available options. In the agriculture layers, for example, you can show the average number of cattle, or crop distribution (wheat, corn, soybeans, cotton).

If farming’s not your thing, take a look at biology. We have lots of gray tree frogs here in Ohio, but they’re not as common in other parts of the country. Wildlife mortality due to lead poisoning is a big problem in California. It’s much less of a problem in Ohio.

Other categories of map layers include climate, environment, geology, history, people (population, health, economy, crime, energy consumption), transportation, and water.

All of the maps can be saved, printed, or emailed.