The Adventures of Mark Twain (1985 film) a bout of one-upmanship, Tom Sawyer, Huck Finn, and Becky Thatcher sneak aboard an airship piloted by Mark Twain in an attempt to become famous aeronauts. Upon discovery, they find that Mark Twain intends to pilot the airship to meet Halley's Comet. Worried that this goal will end in their deaths, the trio learn to fly the ship while conspiring to sabotage the voyage. After discovering the truth behind Twain's journey, the trio recognize their folly, and the group navigates storms and treacherous skies with the help of a mysterious dark figure who turns out to be Mark Twain's dark
Mark Twain Cave and stalactites in large open areas. Mark Twain Cave and Cameron Cave instead have a multitude of narrow, winding passages. The caves are made mostly of a soft limestone called Louisiana Lithographic Limestone and found only in a area around Hannibal and Louisiana, Missouri. The limestone has been estimated by geologists as around 350 million years old, while the cave passages were formed some 100 million years ago. Mark Twain Cave covers some consisting of four entrances and 260 passages, maintaining a year around temperature of . While it is possible that prehistoric Native Americans were aware of the cave,