That really depends on where you live, and what features you describe. Obviously, specific buildings will probably change over 20 years or so, but things like forests, hills, rivers, etc. will remain largely unaffected. Of course, that itself is subject to exceptions, depending on the rate of development of the natural environment around where you live. From my experience (of both cities and country towns in Australia, which may or may not be helpful) over 20 years, large-scale environment features like highway intersections, parks, Central Business Districts, will remain largely unchanged, whereas the suburban and industrial areas can show quite a bit of development. For instance, the Perth CBD today is largely the same as it was in 1990. If you keep in mind the rate and nature of development in your area (plus do a bit of research into currently-trending architectural styles) you should be fine with using your hometown.
Hope this helps :)