The Sequoia Sempervirens is a gigantic Treeship built by the Templars. In the book Hyperion, the ship is prevented from making a trip to Hyperion on pilgrimage, a trip in which the Johnny cybrid and members of the Shrike Church intended on taking part of. Instead, the Yggdrasill took the authorized Pilgrims on the Final Shrike Pilgrimage .
SPOILER ALERT! The section(s) below are MAJOR SPOILERS.
During the Pax Era, the Sequoia was captained by True Voice of the Startree Ket Rosteen. Shortly after Aenea's death, the treeship and its many ergs were used to ferry Martin Silenus' entire building complex on Hyperion to bring him, as well as Raul Endymion and many of Aenea's friends to Old Earth.