The Church in Heaven
Faithful Christians, when they die, go to Purgatory. While we are there our souls will little by little become more healthy and pure, until at last we are fit to live with God in Heaven. Then, when the end of the world comes, we shall be given new spiritual bodies, something like the body of Jesus when he appeared to the disciples on Easter Day, after he had risen from the dead.
Heaven is where God is seen and it will be so wonderful that we cannot possibly imagine it. It will be as different from this life as spring, with its sunny days and bright flowers and singing birds, is different from the cold and gloomy winter. Just as we could have no idea of what the spring is like if we had known nothing else but winter, so we cannot picture Heaven when all we know is this life.
Life there is full of everlasting joy, because the people in Heaven not only see God, but they are also filled with him like a crystal ball is filled with sunlight, except of course that, unlike the crystal and the sunlight, both they and God are alive. To love God and be loved by him and to be filled with him, for ever, will be unimaginable happiness, for he is the source of all true joy and beauty and goodness (Ephesians 3:19). If you possess God, you have all you can ever want.