Recently i was watching black lagoon, in which they board a german sub that was immobilised on the seabed at a depth of 60metres for a peroid of 50 years or so. There was no hull damage and the depth was not too great to cause implosion. Have there ever been real life examples of lost subs being discovered with an atmosphere (albeit toxic) inside?

Jude law: Black Sea, another film with a sub in a similar condition