Cogwheel trains are a type of railway that uses a cogwheel system to climb steep gradients. These trains have a special gear that engages with a toothed rack rail, allowing them to ascend mountains and hills where traditional trains would struggle. This design is particularly useful in regions with challenging terrain. The first cogwheel train was introduced in the 19th century, and they are now popular in tourist areas, such as the Swiss Alps and Rocky Mountains. They provide scenic views and a unique travel experience, making them a favorite among visitors seeking adventure in nature.