Answer:
To unravel me you need a simple key, no key that was made by locksmith's hand. But a key that only I will understand.
You can always see it, but it's too far away to touch. Mountains rest on it, and at sea it surrounds you. What is it?
You can read it both ways, I wearΝΎ One way it's a number, reversed a snare.
What turns from red to black as soon as it touches water?
So cold, damp and dark this place. To stay you would refrain, yet those who occupy this place do never complain.
They are many and one, they wave and they drum, Used to cover a state, they go with you everywhere.