Boulder Dash, originally released in 1984, is one of the big computer-game classics. It is one of the very few computer games ever to be ported from home computers to arcades (contrary to the other way around). The hero of the game is the brave prospector Rockford. He must dig through caves collecting diamonds, while avoiding various types of dangerous creatures and obstacles like falling rocks. He is in constant danger of being crushed or trapped by an avalanche or being killed by an underground explosion. Strategy and planning are the key to master the "physics" of Boulder Dash. Once the indicated amount of jewels have been collected, the door to the mysterious escape tunnel is revealed and Rockford can explore another cave.