I would say it will be the Alps mountain range in Europe.
According to scientists, due to the prevalent effect of global warming, the glacial ice is slow disappearing. It is estimated by 2050 all the glacial ice would be melted completely, and there would not be such interesting and breathtaking view of magnificent white anymore.
It is such a shame, I have always like the panorama because it just looks so great and beautiful. I think I would definitely plan for a trip there before the inevitable happens.
You're right, that would be a terrible loss. And to think 2050 is only just 32 years away.