Frannie, my personal Dane, lives for her walks and we're lucky enough to live relatively close to Tandy Hills (according to people in-the-know Tandy Hills is a "160 acre indigenous remnant of Fort Worth prairie located in the heart of Fort Worth, Texas.") I'm not necessarily a nature buff myself, but I love knowing that I have access to a strip of land that looks almost exactly the same as the land my great-grandmother saw when she came to Texas in a covered wagon.
The place is absolutely breath-taking in the Spring, but there's still a lot of beauty to behold even now that the sun is hot and some of the flowers are wilting.
If you're interested in this sort of thing, there are several geocaches in the area (http://en.wikipedia.org/wiki/Geocaching) just do a google search on Fort Worth geocaches or orienteering. Here's an example of one of the 'clues' that leads to cache hidden in an abandoned vehicle in the valley of the park (followed by several pictures of Fran enjoying herself)...