After thorough research, I could verify that Dead Horse Ranch State Park does indeed have trails where horses are allowed. The park's unique geography offers both easy and more challenging trail options to suit all riders and horses. The authorized and verified trails for equestrian use are as follows:

1. **Lime Kiln Trail**: Providing an excellent view of the lagoon and around the countryside, this trail has a good reputation among horse riders. Lime Kiln Trail follows a former railroad line, making it relatively flat and excellent for horse riding.

2. **Thumper Loop**: This loop trail of about two miles in length is relatively flat and perfect for horseback riding. Riders have reported sightings of different wildlife along the trail, making the ride more interesting.

3. **Quail Wash Trail**: This trail offers moderate difficulty, with a few steep ascensions and descents. However, it's still accessible for skilled horse riders, providing a bit more of an adventurous excursion.

4. **Raptor Hill Trail**: A comfortable and relaxed ride, Raptor Hill Trail is fairly flat and nicely groomed. The trail stretches a modest length of about one mile and is very suitable for horseback riding.

5. **Tavasci Marsh Overlook Trail**: This trail offers splendid views of Tavasci Marsh and the Verde River while enjoy horseback ride. It's one of the park's flat, relatively easy trails for horses.

Please note, always check the official Dead Horse Ranch State Park website or contact the park's visitor center to ensure that these trails remain open for horses at the time of your visit. It's also important to review specific park rules and regulations regarding horse riding for a safe, enjoyable outing.

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.