The idea of living forever in some place called Heaven does not appeal to me.

This place has been called many things, but never Heaven.

It has quite hidden the last square, that we used to call Heaven.

"Do you seek the city of the tower called Heaven?"

Paradise (or often called heaven) is an idea in religion.

"There was a thing called Heaven; but all the same they used to drink enormous quantities of alcohol."

It is what we ordinary people have been used to calling 'Heaven.'

He usually arrives at work an hour or so after me, and spends most mornings in his office, on the phone, calling heaven knows who.

Gritz is talking about a place he calls Almost Heaven.

The tower called Heaven must have been built much later, when the city had already spread wings far along the coast.