JERUSALEM by Alan Moore

All of time already happened once and everything is predestined and time is a solid. But that’s for humans when they’re alive, who have been blessed/cursed with the ability to only see/move in “the special direction”. When you die, and ascend to the accretion of human existence that is the Ghostlands - between life and heaven - you can “tunnel” into the past (or the Ghostworld’s accretion of same) and, as two characters do, you can “walk” forward as far as the end of all time (but it will take you awhile)

Wow, 1971 - I was 4!