Lines spread across wide plains and previously unheard-of rivers and climbed into desolate mountain forests. Most of these lines were never profitable. Therefore, during the 1880s Victoria's rail system became a model railway set that used real engines and carriages. Its imaginative purpose, as opposed to its practical purpose, was to give Victorians the feeling that they could travel safely from anywhere in the colony to anywhere else. And this remained true until the late 1960s, when suddenly the railway system began to make huge losses and politicians began planning ways of shutting it down.
Railway trains are symbols of power, especially when carried along by steam engines.
But railways are also a symbol of domesticity. Boarding a passenger train, ticketed passengers know their destinations. It doesn't crash, except in the most exceptional circumstances. A land filled with railways, like the USA of my atlas, is a settled land. People can move as they like.