The Cradle

The Cradle is a structure located near Echo Mesa on Io. It is a relic of the Traveler during its partial terraforming of the moon, and is a site of holy significance to many Guardians.

A year after the conclusion of the Red War, the Guardian was summoned to Io by visions, and witnessed the Cradle emitting enormous pulses of Light. It is considered likely that the Cradle, and Io itself, remain connected to the Traveler through it's remnant energies.

When the Pyramids returned to the Sol System, one massive Pyramid and a fleet of attendant vessels settled over the Cradle. The Guardian was dispatched to investigate the Cradle and search for Eris Morn, who had ventured inside. In the hollow at the center of the Cradle, Eris and the Guardian discovered a "tree of silver wings" with a seed beneath its roots.

Trivia

 * Bungie Senior Concept Artist Sung Choi uses the name "Cradle" in an Artstation post featuring concept art of the structure.
 * The name was confirmed in Season of Arrivals.
 * Locations within the Cradle are, in gameplay, actually underneath the Cabal structure adjacent to Giant's Scar.