The Anahata chakra is physically positioned at the heart region.
Anahata is associated with the ability to make decisions outside of the realm of karma. In Manipura and below, man is bound by the laws of karma, and the fate he has in store for him. In Anahata, one is making decisions, 'following your heart', based upon one's higher self, and not from the unfulfilled emotions and desires of lower nature.
It is also associated with love and compassion, charity to others, and forms of psychic healing.