Greetings!
A thesis statement should be more than a summary of your topic. Generally, a thesis statement takes a position on a subject that can be argued on either side. It is normally narrower than the very broad statement you made. It helps if your thesis statement presents an original idea that is persuasive.
Notice how adding specific details makes an opening more interesting than a a generic statement that could describe just any place:
"Despite the fragile environment, unrelenting mosquitoes and unpredictable weather,
the fascinating rock formations of Terelj make it the most worthwhile tourist destination in Mongolia."
Even though it's not a very controversial subject, one could take the opposite position and argue that Terelj is not the most worthwhile tourist destination -- so that statement does take a position which the rest of the paper could support.
I hope this helps!
Thanks,
Sarah, EssayForum.com
Sarah, EssayForum.com