Describe a theme park ride that has a constant speed but changing velocity?

A Ferris wheel is a good example of a ride that would change velocity but not speed. Because it moves around in circles, it changes direction but the speed remains the same.

The only difference between speed and velocity is that velocity also includes direction, so if the speed is the same but the velocity is changing, that means that the direction is changing on the ride, but the speed is staying the same.