OMSI: The Bus Simulator is a highly detailed simulation game, but it is . While "free" links often appear in search results, these are typically pirated copies that can contain malware or lack essential updates and mod support.
Epic Games Store has given away Bus Simator 16 for free multiple times. It’s not OMSI, but it scratches the itch. omsi bus simulator free download full version for 14 top
Here is a story about the journey of a young simulator fan discovering the world of OMSI. The Route to Spandau not available as a legitimate free download OMSI: