SB 11.24.12

devānām oka āsīt svar
 bhūtānāṁ ca bhuvaḥ padam
martyādīnāṁ ca bhūr lokaḥ
 siddhānāṁ tritayāt param
devānām — of the demigods; okaḥ — the home; āsīt — became; svaḥ — heaven; bhūtānām — of ghostly spirits; ca — and; bhuvaḥ — Bhuvar; padam — the place; martya-ādīnām — of ordinary mortal humans and other beings; ca — and; bhūḥ lokaḥ — the planet called Bhūr; siddhānām — (the place) of those striving for liberation; tritayāt — these three divisions; param — beyond.
Heaven was established as the residence of the demigods, Bhuvarloka as that of the ghostly spirits, and the earth system as the place of human beings and other mortal creatures. Those mystics who strive for liberation are promoted beyond these three divisions.

Planets such as Indraloka and Candraloka are meant for the heavenly enjoyment of the most pious fruitive workers. The highest four planets, however, Satyaloka, Maharloka, Janoloka and Tapoloka, are meant for those who are most perfectly endeavoring for liberation. Caitanya Mahāprabhu is so inconceivably merciful that He is promoting the most fallen victims of Kali-yuga beyond these four planets and even beyond Vaikuṇṭha, to the supreme planet of Lord Kṛṣṇa in the spiritual sky, called Goloka Vṛndāvana. Śrīla Bhaktisiddhānta Sarasvatī Ṭhākura explains that heaven is the residence of the demigods, the earth is the residence of the human beings, and in between is a temporary residence for both classes of beings.