Which gives you a frame of refernce for your speed when your are riding in a train?

When riding in a train, your frame of reference for speed is typically the scenery outside the window. As the train moves, you can observe the relative motion of trees, buildings, and other objects passing by, which helps you gauge how fast you are traveling. Additionally, the train's speedometer display, if available, can provide an exact measure of your speed. The sensation of movement and the sound of the train also contribute to your perception of speed.