If it was invaded many times over 3000 years, i don't see how it could stay the same. Even without being invaded, a lot will change over that long a period; pick an area and subtract 3000 years - whatever area you choose, you'll find a lot has changed.
To answer your second question, i'd let it stay the same, but i'm not the invader type. Someone like me would never invade anyplace, so i guess my answer to that question is pretty irrelevant. I think a person who thought so little of a civilization that they would invade them, would probably make SOME changes - at least a few.
ETA - I agree. Egypt has changed since then but yes, it's conquerors seem to have respected their history.
To answer your second question, i'd let it stay the same, but i'm not the invader type. Someone like me would never invade anyplace, so i guess my answer to that question is pretty irrelevant. I think a person who thought so little of a civilization that they would invade them, would probably make SOME changes - at least a few.
ETA - I agree. Egypt has changed since then but yes, it's conquerors seem to have respected their history.