Secret passage

The Secret Passage is the hidden tunnel that runs from a concealed door on the western slope of the Lonely Mountain down into the great bottom-most cellar where Smaug lies on the treasure of Thror. It is the key to the entire quest of Thorin and Company, for without it the dwarves would have had no hope of approaching the dragon's hoard except through the heavily guarded Front Gate. The passage was built by the dwarves of old at the height of their wealth and skill, and its existence was recorded only on Thror's Map, in moon-letters that could be read only under a moon of the same shape and season as when they were written.

Discovery and Opening

The existence of the Secret Passage was first revealed to the company by Gandalf, who pointed out the rune on the west side of Thror's Map and the hand pointing to it, marking a hidden passage to the Lower Halls. The wizard explained that the door was only five feet high and three feet broad, too small for Smaug to use, and that it had been made to look exactly like the side of the Mountain, a typical dwarves' method of concealment. Later, at Rivendell, Elrond read the moon-letters on the map by the light of a crescent moon: "Stand by the grey stone when the thrush knocks, and the setting sun with the last light of Durin's Day will shine upon the key-hole." Thorin identified Durin's Day as the first day of the dwarves' New Year, when the last moon of Autumn and the sun are in the sky together. After weeks of fruitless searching on the western slopes, Fili, Kili, and Bilbo discovered a narrow track leading to a small grassy bay high on the mountain-side, where a smooth rock-face stood without joint or crevice. There they waited, and on the last day of autumn, as the sun sank, a thrush knocked a snail against a grey stone. A red ray of the setting sun shone through a rent in the cloud and fell on the rock-face, and a flake of rock split from the wall. Thorin inserted the silver key that had come with the map, and the door swung inward, revealing darkness that flowed out like a vapour.

Bilbo's Descents and the Encounter with Smaug

The passage was straight as a ruler, smooth-floored and smooth-sided, going with a gentle never-varying slope down into the blackness below. Bilbo crept through the enchanted door and stole into the Mountain, slipping on his ring and moving noiselessly. As he descended, the air grew warm, a red glow appeared ahead, and he heard the gurgling snore of a vast animal. At the end of the tunnel, an opening of the same size and shape as the door above gave onto the great bottom-most cellar, where Smaug lay asleep on countless piles of gold and jewels. Bilbo grasped a great two-handled cup and fled back up the tunnel, but the dragon woke and missed the cup, and his rage shook the mountain. On his second visit, Bilbo found Smaug pretending to sleep, and engaged him in riddling talk, during which he discovered a bare patch in the hollow of the dragon's left breast. The dragon spouted flames after him as he fled, singeing the hair on the back of his head and his heels. After the dwarves had shut the door, Smaug smashed the mountain-side, shattering the wall and cliff and blocking the upper end of the tunnel with broken rock, so that neither key nor magic could ever open that door again.

Consequences and Significance

The destruction of the Secret Passage trapped the dwarves inside the Mountain, forcing them to descend through the treasure hall and find their way out through the Front Gate. This led them to the watch-post on Ravenhill, where they learned of Smaug's death and prepared for the siege that followed. The passage was the only means by which the company could approach the dragon without facing the Front Gate, and its discovery and use set in motion the central conflict of the quest. It was also the site of Bilbo's most courageous act, the moment when he fought the real battle in the tunnel alone before ever seeing the vast danger that lay in wait. The Secret Passage thus stands as the threshold between the world of the quest and the dragon's lair, the point at which the adventure turns from journey to confrontation.