50 levels in 4 environments, unlocked one by one. stations, tunnels and the scenery are fixed, only track pieces can be interacted with. the train only leaves when you click a button, but even if it crashes, level reset leaves pieces as they were, no need to start over. solved levels remain solved for later as well.
not many mechanics to speak of, but besides some elevated terrain, crossing tracks play a major part. arrows indicate the direction the train will take the first time it passes over them, then they switch to the other track for next time (and possibly another if it's a 3-way thing). stop/go signs with numbers indicate how many passes are needed for the switch to happen.
controls are mouse-based, but the keyboard also works for bringing up the menu, restarting a level, starting the train or zooming in and out, which was patched in after release as a must-have feature to properly see some of the levels. left click swaps tiles, mouse wheel rotates what's under the cursor. holding it moves the camera around, right click rotates it, but restarting a level resets the camera too. 2x speed was another post-release addition, also necessary because the train takes a while to do its thing on some levels.
lovely model railway aesthetics with planes flying around, ships on the water, pretty cool. nice music, separate volume settings, resolutions, windowed mode, shadow and v-sync toggles and languages, but only volumes are available while playing. there's a level select screen, also only through the main menu's play button, and level numbers aren't visible anywhere else.
it's all very relaxing, a bit tricky at times with all the loops, so if you're in a conducting mood, choo-choose this. an update even added a level editor with workshop support to provide longevity.