The old men say, that before this stone guards passionately worshiped. From what they conceived a great power and stones soared into the sky. Pilgrims could not let them fly away and built a tie-up (chain) to keep with them a strong magic. But energy is not enjoyed such treatment and pretty quickly she began to leave custody.
Now, occasionally someone will remember this legend, and will lift up prayers guards. But their number is negligible, and the energy does not come back at all in custody. It is enough only for one.