I think about the coolest place I have ever blazed was just recently I went on a cruise. We had a nice room on the 8th deck with a balcony overlooking the sea with a few chairs out there. Picked up some cuban cigars in Mexico and rolled some blunts out of a cuban, chilled on the balcony and just looked out on the sea for miles, the horizon and the sky. Shit was so nice, expecialy with the nice breeze blowing. Not to mention basically directly above my cabin was a bar, so I also had a margarita in the hand not holding the blunt.

Besides that my next favorite place to burn a session is at the end of a long hike on top of a mountain, one of the greatest places was at a glacier in Montanna. Here is a pic of the individual glacier we chilled at, we were sitting down by the blue water, the pic is from the distance http://www.starrywonders.com/glacier1.jpg
Actually looking at the pic a bit more, might have been up by that mass of snow in the top right corner of the pic, there is another glacial lake up there that can't be seen in this pic.