This article explains how to:
Save Google Earth data, so that you can access it offline.
Google Earth works best with a live internet connection. You can, however, cache (save) small amounts of data that you can access when you're offline.
To do so, log on to the internet and visit the imagery you'd like to view while you're offline. Please pay attention to the Streaming indicator, which appears just below and a little to the right of your images. When this indicator has reached 100% for the imagery you're viewing, Google Earth has gathered all available data for that specific altitude and settings, so you can disconnect from the internet.
Please remember that once you're disconnected, you'll be able to view cached areas only.
