In Paris but not in France, the thinnest of its siblings.

Answer: I

More Difficult Riddles with answers

More Difficult Riddles

In the evening I'm long, in the morning I'm small; When seen in a ballroom, I'm nothing at all.
In the forest, this blends in just right, but every December it is covered with lights. What is it?
In the land of the green glass door there are riddles but no answers, sheets but no blankets, and books but no words. Name something found in the land of the green glass door.
In this place, people lie, people cry, and people ask why. In this place, people sleep, people weep, and people's solitude, they keep. What is it?
Iron roof, glass walls, burns and burns and never falls.
It can cause deflation of tires when dropped from the rear of spy cars.
It can pierce the best armor and make swords crumble with a rub, yet for all its power It can't harm a wooden club.
It can't be seen, can't be felt, can't be heard, and can't be smelt. It lies behind stars and under hills, And empty holes it fills. It comes first and follows after, Ends life, and kills laughter. What is it?
It cannot be seen, cannot be felt, Cannot be heard, cannot be smelt. It lies behind stars and under hills And empty holes it fills. It comes first and follows after, Ends life, kills laughter.
It doesn't live within a house, nor does it live without. Most will use it when they come in, and again when they go out.
It flies when it's on and floats coming off.
It floats over the land, It cuts the tallest mountain, Its voice is like a fountain, Its body like a snake, Will flow into a lake.