As an image talks more than 1000 words....here are comparisons (images) of many glaciers around the world some years ago and today.
Tip:
You have 2 items per glacier: the Overlay, that shows you the pictures and the Placemark that take you to the location.



So go to the placemark and then check the overlay to see the picture. When you want to go to another location uncheck the overlay, go to a new location an check that new overlay to see the new picture.

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