Google Earth (“GE”) is a wonderful tool for trip planning. However, there's a rather annoying bug for alpine climbers - mountain tops that are especially pointy can sometimes appear much flatter than they are in real life. This can make a technically difficult summit appear to be just a casual walk up, which could obviously get you in trouble if that's the only navigation tool you’re using. Let's look at an example.

Here is a photo of Mt. Thielsen in southern Oregon, a popular route. This view, from the Pacific Crest Trail, clearly shows the dramatic and steeply pointed summit block. (The route goes up the right skyline.)

And, here's what the summit block looks like close up.

Definitely not a casual walk up. Most people use ropes and rappel. What’s not shown is the thousand or so foot drop just behind the guy in the red shirt.

Here's a topographic map that shows the true steepness.

Let's compare that with a few screen grabs from Google Earth of Mt. Thielsen.

Wait, what happened to the pointy summit? Looks like a casual stroll to the top!

More of a close-up . . .

Here’s a view from the increasingly-excellent-if-slightly-expensive mapping software Fatmap. Fatmap uses a different 3D terrain model than Google Earth, and the summit appears much as it does in real life.

However, Google Earth doesn’t “flatten” every pointy peak. Here's a final example, the iconic Matterhorn Near Zermatt, Switzerland - looks perfect!

So, a good rule of thumb: If you’re climbing something steep but it doesn't look that way on Google Earth, always check other photos and topographic maps to make sure you have a true understanding of the terrain.