Adelsberg, a small market town of Carniola, Austria, on the Semmering railroad, midway between Laybach and Trieste, near a celebrated cavern, which has five main divisions. The first, called Neptune or Great Dome grotto, traversed for the length of 400 feet by the Poik river, and rich in stalactites, constitutes the old part of the cavern, which has been known for upward of 000 years. The entrance to the new parts of the cavern was accidentally discovered in 1816. This leads in the first instance to the second main division, called the emperor Ferdinand's chamber, with large corridors called the ball-room and the circus, where annual festivals take place, and that of Calvary, a mound formed by the ruined columns of rocks more than 200 feet high. The third main division consists of two basins of water called the dropping well and Tartarus. The fourth main division, the archduke John grotto, opens behind a curtain of transparent spar, and contains other shapes called Little Curtain and Gothic Hall. The fifth main division, the Francis Joseph and Elizabeth grotto, explored for the first time in 1857, discloses a range of chambers with brilliant and fantastic shapes, and a picturesque elevation called Little Calvary. About three miles from Adelsberg is the Black or Magdalen grotto, through which runs a river.

Here was first discovered the proteus anguinus, an animal half fish, half lizard, and eyeless. The Poik cavern, a mile from the last-named grotto, is only accessible by the aid of a rope, and remarkable chiefly for the dashing of the river over the rocks.