Which sentence states a fact?

 - The Great Sphinx is the most interesting Egyptian landmark.
 - The Great Sphinx was built more than 4,500 years ago and is located in Egypt.
The second sentence states a fact.
The Great Sphinx was built more than 4,500 years ago and is located in Egypt.
It can be proved by reading a history book about the Great Sphinx.
The first sentence states an opinion.
The Great Sphinx is the most interesting Egyptian landmark.
Most interesting shows what a person believes, thinks, or feels. Another person might have a different opinion about what makes one landmark more interesting than others.