To Heaven by Heaven

Speaking about heavens in plural in religion, we do not refer to some place in the universe, we refer to something much bigger and more difficult to define with our limited human concepts.
Nevertheless, in christianity the highest level is the seventh heaven, in which God can be seen and where anything is possible. That there is a place in God for christians .

 Antonio Campi Les Mystères de la Passion du Christ (detail) 

In hinduism the seven upper lokas (worlds) are:
Bhurloka (earth), Bhwar-loka (space between earth and the sun, inhabited by semi-divine beings), Swar-loka (region between the sun and polar star, the heaven of the god Indra), Mahar-loka (the abode of great sages and saints), Jana-loka (abode of the sons of the god Brahma), Tapar-loka (abode of other deities), and Satya-loka or Brahma-loka (abode of Brahma, where souls are released from the necessity of rebirth).
Brahmaloka is the highest heaven, where fortunate souls repair after death and enjoy spiritual communion with the personal God, and at the end of the cycle attain liberation. Corresponding to every world here, there is a corresponding sheath of consciousness within every human being, reflecting the correspondence between the microcosm and the macrocosm.

Islamic texts refer to several levels of heaven: Firdaus or Paradise, 'Adn, Na'iim, Na'wa, Darussalaam, Daarul Muaqaamah, Al-Muqqamul, Amin & Khuldi. Each Heaven or “ss-samawat” consisting of seven levels, the first and lowest level of as Dunyah, which covers the known universe and all within it. The highest level is the seventh heaven, in which God can be seen and where anything is possible. The parable of the Garden which the righteous are promised!- beneath it flow rivers: perpetual is the enjoyment there of and the shade therein: such is the end of the Righteous; and the end of Unbelievers in the Fire.(Quran013.035)

But while we are on the earth any concepts about heavens remain only the concepts for us. And while we are here - heaven does not belong to the geography of space, but to the geography of the heart. God instead never passes and all of us exist because of his love. We exist because he loves us and God receives in his eternity what now, in our life, made up of suffering and love, of hope, of joy and sadness, grows and comes to be. All human life are "in his eyes".
And Katha Upanishad says: "When all the desires that dwell in the heart fall away, then the mortal becomes immortal and here attains Brahman."