Large as a mountain, small as a pea, Endlessly swimming in a water-less sea.

Answer: asteroids

More Difficult Riddles with answers

More Difficult Riddles

Lazy Larry agreed to work on a job for his brother-in-law for thirty hours at eight dollars an hour, on the condition that he would forfeit ten dollars per hour for every hour that he idled. At the end of the thirty hours Larry wasn't owed any money and didn't owe his brother-in-law any money either. How many hours did Larry work and how many hours did he idle?
Left to right I’m quite bright. Right to left I might bite.
Lily is a lilypad in a small pond. Lilly doubles her size each day, On the 20th day she covers the whole pond. On what day was Lily half the size of the pond?
Lives without a body, hears without ears, speaks without a mouth, to which the air alone gives birth. What is it?
Long and slinky like a trout, never sings till it's guts come out.
Long legs, crooked thighs, little head, and no eyes.
Look into my face and I'm everybody. Scratch my back and I'm nobody.
Looks like water, but it's heat. Sits on sand, lays on concrete. A play on the eyes, but it's all lies.
Man walks over, and man swims under. In times of war, it can be burned asunder. What is it?
Many have heard it, but nobody has ever seen it. It will not speak until spoken to. What is it?
Many hear me, but no one sees me, and I only speak when spoken to
Many-manned scud-thumper, Maker of worn wood, Shrub-ruster, Sky-mocker, Rave! Portly pusher, Wind-slave. What am I?