Google Earth can be very useful for hiking and backpacking. You can usually find trail data online, and get a good idea of elevations and distances before even hitting the trail.
It can open kml/kmz files, and other mapping formats (like gpx). I was looking for a Northern Loop path, and eventually found one at GPSfly. It had a few extra side paths and didn’t fully go from Sunrise to Sunrise, so I opened it with WTracks and cleaned it up so the total distance would be more accurate.
After importing the edited gpx into Google Earth, I turned on the Parks/Recreation Areas in the Layers panel to see what would show up, and the results were mixed.
A few campsites looked good, a few were missing, and Berkeley Park was obviously in the wrong spot. It did show a few waterfalls and Ranger Stations which was nice.
I ended up using the map on the NPS site to cross-check where the campsites were supposed to be, and then manually added the camps to Google Earth.
There are various Wonderland Trail elevation profiles online, but I did not find a Northern Loop one that I liked. So, I made my own. To view the profile in Google Earth, right-click on the path in the map (or side panel), and select Show Elevation Profile.
In addition to showing elevation and distance, you can click + drag on the profile to select a portion of the trail. This allows you to easily measure distances between points on the map.
For example, I selected the trail from Yellowstone Cliffs to Fire Creek. Directly above the elevation profile (in the grey area) it gives you distance, elevation gain/loss, and other data. I used this to measure distances between camps and decide how far we wanted to hike each day.
A tour is a virtual fly-through following a path. You can control zoom and speed options of the tour by clicking Tools > Options. Click the Touring tab to change settings.
Back in the main window, select a path and press the Play Tour button (which actually plays and records at the same time). This will start following your path.
When the tour has completed, click the Disk icon to save the tour, so you can play it later.