FreeTrain is a game by Kohsuke Kawaguchi, written in C# using Microsoft’s .NET platform. It is inspired by the A-Train series of games which focuses on a combination of train and business simulation. FreeTrain is the quintessential sandbox game. First of all, you start in a literal sandbox: a flat barren piece of land greets you when starting a new game. After that, it’s completely up to you to create your world, including natural features such as mountains or lakes.