One of the coolest things in nature I saw was Mount Elbrus, the highest peak in the Caucasus Mountain range, which stands at over 18,500 feet! On a clear day in Batumi, I faintly saw the outline of Elbrus on the horizon, even though it is 125 miles away.
My favorite part about Georgia's nature is how you can see the ice-capped mountains while standing on a near-tropical beach. The contrast is truly amazing.