tirthanam srotasam ganga
samudrah sarasam aham
ayudhanam dhanur aham
Among sacred and flowing things I am the holy Ganges, and among steady bodies of water I am the ocean. Among weapons I am the bow, and of the wielders of weapons I am Lord Siva.
Lord Siva used his bow to completely cover with arrows the three demoniac cities built by Maya Danava.