It's fun to look at them, and imagine what's there. It can be surprising to study maps of areas that you think you know well; sometimes you find your perceptions of place are a bit skewed. The blank spaces on street maps can suggest worthwhile areas to explore, and a good trail map can save your befuddled behind. Anyhow, the USGS makes about the best maps around, and I recently stumbled onto the UNH Library's online treasure trove of old USGS maps of New England. It's way cool. The quadrants covering Nashua aren't labeled as such, but by other neighboring towns which they also cover.