Riddle

A circle of stones, never in rows. Stacked one on the other, mystery it sows. What is it?

Choose an answer

A.A pyramid
B.A burial mound
C.A castle ruin
D.Stonehenge
Hint: It's a word with 10 letters, starting with "S".

Answer

Stonehenge

Why this is the answer

Stonehenge is the famous prehistoric circle of massive standing and stacked stones whose original purpose remains a mystery.

This riddle is filed under "What Am I?" Riddles and rated Medium.