In
Dan Simmons's epic
Hyperion tesseralogy, the Time Tombs are enigmatic structures discovered by the first settlers on the planet Hyperion. Located in a valley near the
Pinion Plateau on the continent of
Aquila, the Tombs are believed to have been sent back in time from the far-distant future. The
Church of the Final Atonement regularly sends pilgrims to the Tombs as an offering to the
Shrike.
Warning: Spoilers follow.
At the time of the last Shrike Pilgrimage and the other events leading up to the Fall (that is, at the time of Hyperion and The Fall of Hyperion) precious little was known about the Tombs. They are surrounded and protected by the time tides, waves of anti-entropic flux which make their time travel possible. Because of the tides, not all of the Tombs are visible in present reality at all times. During the last Pilgrimage, the Tombs "opened" -- that is to say, came into alignment with the time flow of the rest of the universe. After the Fall, some remained open, while others ... did other things.
The Time Tombs are as follows: