Impossible Engineering: Season 4 (Season 4: Extreme Railroads)
This season started on May 17, 2018. The table lists episodes with recorded air dates up to September 28, 2026.
| Ep | Title and air date | My place |
|---|---|---|
| 1 | Deadliest Trains · 42 min | |
| 2 | World's Fastest Trains · 42 min | |
| 3 | Mega City Trains · 42 min | |
| 4 | Trains of the Abyss · 42 min | |
| 5 | Monster Mountain Trains · 42 min | |
| 6 | Trains of Deadly Seas · 42 min |
