Har Sinai, the place where Moses brought down the Ten Commandments circa 1280 bce, is situated in the southern corner of the Sinai Peninsula, Egypt.
Coordinates: 28°32′23″N 33°58′24″E
We lived in Di Zahav, Sinai for 9 months from May 2013 to early Feb. 2014. I have done a great deal of research on the Exodus story, תכלת etc.
P.S. I believe Shavuot is the most important of the Jewish Holy Days. Why? No Moses and the Ten Commandments = No Western Civilisation.