I recently shared an app called MAPS.ME (http://www.vingle.net/posts/613588) that lets you have an offline map and thought it would be a good idea to share a similar feature on Google Maps that you can use if you already have the app on your device and don't want to install a new one.
With the Maps app, you are able to select an area of a map to save on your phone for offline use. You are limited to it being 50 km x 50km. In order to do this, you do the following:
1.) Search for your desired location
2.) Pull up the place info sheet at the bottom of the screen, and touch the menu three vertical dots in the top right corner.
3.) Select Save offline map to save the selected area of the map. (Sign into your Google Account, if you haven't already.)
4.) Only what's on the screen will be saved. Adjust the map by moving it and zooming in or out, as needed, then touch Save.
5.) Name the map, and then touch Save.
After a few moments, you'll see a message confirming that the map area has been saved.