Why is my Kia Picanto vibrating when I drive at high speeds?

I recently noticed that my Kia Picanto starts to vibrate when I drive over 60 mph. What could be causing this and how can I fix it?

If the vibrations are accompanied by a humming noise, it could indicate a problem with the wheel bearings. Have a mechanic check them and replace if necessary.

If the vibrations only occur when braking, it could indicate warped brake rotors. Have them checked and replaced if necessary.