RollerCoaster Tycoon

RollerCoaster Tycoon is a construction and management simulation game in which players build and run an amusement park. Written almost entirely in x86 assembly by Chris Sawyer, the game was a critical and commercial phenomenon on release, selling over 4 million copies. Players design roller coasters, manage staff, set prices, and keep guests happy — all while watching their parks grow from small fairgrounds to sprawling theme park empires. It is widely regarded as one of the greatest management simulation games ever made.