KV17 plunges 137 meters into the bedrock, descending through corridor after corridor along an axis that wiggles before it steepens, then opens into hall after carved hall. Reliefs cover nearly every surface in all but two of its chambers. Seti stands before Ra, before Hathor, Horus and Neith, his figures cut in delicate raised relief and washed in color. The ceiling of the burial chamber bears a vaulted astronomical sky, mapping the circumpolar stars and constellations. Beneath the spot where the sarcophagus once stood, a mysterious tunnel slopes still deeper into the rock. Excavators have chased it down 174 meters, through two staircases, only to find it stop abruptly at the bottom of the second. No one knows for certain why it was cut.

Belzoni was no trained scholar. Born in Padua, he had worked English fairgrounds as "the Patagonian Samson," lifting platforms full of men, before turning his strength and showmanship toward Egypt on behalf of the British consul Henry Salt. He had a genius for moving enormous objects, and an equal talent for damage. To copy the reliefs he made "squeezes," pressing wet wax and plaster against the carvings; when they dried, they pulled the ancient color away with them. He hacked whole sections of relief off the walls to ship to Europe. He cleared rubble that had been holding back flood water, and in later years the tomb flooded, ruining stretches of the entrance decoration he had so admired. The hands that opened the finest tomb in the valley also helped to scar it.

Seti's tomb was dismembered piece by piece and carried to the museums of the West. The pharaoh's sarcophagus, carved from a single block of translucent alabaster and covered inside and out with the spells of the Book of Gates, was offered first to the British Museum. They balked at the price. In 1824 the architect Sir John Soane bought it instead for 2,000 pounds and installed it in the basement of his London house, where it still glows when lit from within and remains one of the museum's treasures. Champollion, who had cracked the hieroglyphic code on the Rosetta Stone, cut a painted panel from a corridor wall during his 1828 expedition. Other fragments went with his colleagues. Today pieces of KV17 sit in the Louvre in Paris, the Egyptian Museum in Florence, and the Neues Museum in Berlin.

When Belzoni reached the burial chamber, the alabaster sarcophagus was there, but the king was gone. Seti's mummy had been moved long before, by ancient priests trying to protect their rulers from the wave of tomb robbery that swept Thebes at the end of the New Kingdom. They eventually hid him, along with three dozen other royal mummies, in a cliff cache at Deir el-Bahari, where he was rediscovered in the nineteenth century with his face remarkably preserved. The tomb that had been built to keep him for eternity could not, in the end, hold him. Modern conservators have laser-scanned its walls and built full-scale facsimiles of two of its halls, an attempt to preserve in copies what the original has slowly lost. As of 2025 the real tomb is open again to visitors willing to make the long descent.