However, the Hispanic community (particularly forums like EliteGuias and ZonaSubnautica ) has produced for old portable versions. If you do find an ISO of the original game, you can apply a Spanish language pack manually.
Before we hunt for the "portable free" version, it is important to understand why the original RCT is still superior to its modern sequels.
Which option sounds appealing to you?
Instead of risking a malware infection, you can play the game legally, safely, and very cheaply through official modern platforms:
While there isn't an official "portable" version of the original RollerCoaster Tycoon 1