Riddle #1050

Slayer of regrets, old and new, sought by many, found by few. What am I?

Two sisters we are, one is dark and one is fair, In twin towers dwelling we're quite the pair, One from land and one from sea, Tell us truly, who are we?

I am a 5 letter word. Take away the first letter and I am a country's name. Take away the first two letters and I become the opposite of the 5 letter word. Who am I?

I soar without wings, I see without eyes. I've traveled the universe to and fro. I've conquered the world, yet I've never been anywhere but home. Who am I?

What always runs, but never walks, often murmurs, never talks, has a bed, but never sleeps, has a mouth, but never eats?

If will follow you for 1000 miles but not miss home. It desires neither food nor flowers. It fears not water, fire, knives, nor soldiers. But it disappears when the sun sets behind the western mountains. Who Am I?

What has roots as nobody sees, Is taller than trees, Up, up it goes And yet never grows?

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?

I am the biggest alphabet, as I contain the most water in the world. Who am I?

I am the building with number stories. Find me who am I?

I have all the knowledge you have. But I am small as your fist that your hands can hold me. Who am I?