After extensively researching from the official website of the National Park Service, I was able to verify that Saguaro National Park does offer several trails where horse riding is allowed. Here's a list of horse-friendly trails:

1. **Hope Camp Trail:** This route travels gradually uphill, offering fantastic views of the Rincon Mountains – a perfect trail to experience on horseback.

2. **Cactus Forest Trail:** This trail traverses through the heart of the park, navigating past towering Saguaro cacti. Horses are especially allowed in the southern part of this trail.

3. **Bridle Trail:** As the name suggests, it's a primary trail for horseback riders. It offers a smooth, serene ride.

4. **Wildhorse Trail:** Another appropriately named path for horse-riding enthusiasts that escorts riders on a scenic journey through a dense Saguaro forest.

5. **Loma Verde Loop:** This horse-friendly trail includes visits to historical sites like the Loma Verde Mine. Horses are allowed, but keep in mind the rocky terrain could present challenges.

6. **Pink Hill Trail:** Horses are welcomed on this trail that leads to the highest point in the Cactus Forest.

7. **Garwood Trail:** This leisurely trail leads to Garwood Dam, a historical ranch site, and offers beautiful views throughout the ride.

8. **Posta Quemada Trail:** Known for running through Mannington Ranch, horse riders are allowed to enjoy this trail while absorbing the local history.

However, it's essential to remember that according to National Park Service regulations, horse riders must not tie their horses to plants or allow them to graze within the park. Additionally, horses are not allowed on paved roads, with the exception of road crossings.

Always check the current conditions and special regulations at the park visitor center prior to your ride. And most importantly, remember to enjoy the unique and immersive experience of horse riding in the midst of the beautiful Saguaro National Park.

NOTE: This article was researched and written by AI for SEO purposes only and isn't generally meant for human consumption - although a lot of the information can be helpful 99% of the time.  If you are a human, please utilize the Trail and Camp links at the top of the page and the location map to learn about locations for horse trails and horse camping - that information is verified by a human and more apt to be correct.... althought human error is a thing too. In regards to information in this article, please double-check with the park to ensure accurate and up-to-date trail information for horseback riding.