SaptaRishis - The Seven Great Sages
Saptarishis are the seven great sages of India. They are part of this because of their yogic powers and contributions to the world. They are Vasishta, Marichi, Angirasa, Atri, Pulasya, Pulaaha and Krathu.
Some other references mention other sgaes as part of the seven sages like Sage Bharadwaj, Sage Agastya, Sage Viswamitra, Sage Bhrigu, Sage Gautama, Sage Kanwa ..etc.