Answer:
A mile from end to end, yet as close to as a friend. A precious commodity, freely given. Seen on the dead and on the living. Found on the rich, poor, short and tall, but shared among children most of all.
What flies around all day but never goes anywhere?
Jack and Jill when up the hill jack fell down
Inside a great blue castle lives a shy young maid. She blushes in the morning and comes not out at night.
Upon me you can tread, though softly under cover. And I will take you places, that you have yet to discover. I'm high, and I'm low, though flat in the middle. And though a joy to the children, adults think of me little.
They are many and one, they wave and they drum, Used to cover a state, they go with you everywhere.