Translation of ride a horse in Spanish

I hope you can understand the corrections this way... Two small errors. let me know if there is a word or sentence or phrase that you didn't understand! I will try to think more on the "since" question...
I wish you would help me to improve my Spanish. I am studying law in Germany and I am trying to learn Spanish. I hope you can help me and I could help you to learn German. Have a great day.
The next day we had to take the bus in order to get back to the airport in Calama. When we arrived at the airport was empty and no counter was open yet. We had to wait for 4 hours.