Wikipedia:
In many religions, Heaven is a realm, either physical or transcendental in which people who have died continue to exist in an afterlife.
Heaven is often described as the holiest place, accessible by people according to various standards of divinity, goodness, piety, faith or other virtues.
Gloria Estevan:
Heaven's what I feel when I'm with you
I went to church for a Sunday service at 9am nearby my house and I remembered words the priest said in her 40 minutes sermon.
Heaven is when you feel God's existence. Whenever and wherever you are with if you feel Him in your heart that's where the heaven is.