If you have a smart phone then there are some really good options, especially for areas where good paper maps aren't available. If you have android, my favorite is Backcountry Navigator. The have many different map sources, including caltopo, Accuterra and openandro maps that allow you to download maps of entire states for offline use. These maps are often more current and detailed than USGS maps. My preference is to carry all of the following; 1) basic forest service map, 2) a ranger district map (which has contour lines) for the area I will be hiking and 3) my phone with gps and backkcountry navigator. 4) on rare occasion I'll download a usgs map but this rare since the only reliable information they have is topography and not current roads, trails,etc.