The Kursk has surfaced for the first time since it sank with the loss of all hands.
The glass from its conning tower is blown out but the seal of the Russian eagle is intact.
The submarine broke the surface at the dock in Roslyakovo, near Murmansk.
Prosecutor-General Vladimir Ustinov and about 40 investigators donned gas masks for their first tour of the submarine.
It is believed that toxic gases built up in the submarine during its 14 months at the bottom of the Barents Sea, where it sank during naval manoeuvres in August 2000, killing all 118 crewmen aboard.
Deputy Prime Minister Ilya Klebanov, who is responsible for the Kursk salvage operation, says it will take up to three days to dry out the submarine.
He said "nothing new will be found in the raised submarine" that could help "in understanding the causes of the Kursk catastrophe".
Many Russian and foreign experts say the initial explosion was sparked by an internal malfunction, but government officials say the Kursk may have collided with another vessel or World War II mine.
The submarine was raised and towed to shore in a risky, complicated operation that cost the Russian Government some £45m.
The submarine's shattered first compartment, where the torpedoes were located and which may contain vital clues to the cause of the disaster, was cut off and left at the bottom of the sea for collection next year, if possible.