Siddula Gutta, also known as Sri Navanatha Siddeshwara Temple, is one of the most famous pilgrimage and tourist destinations in Armoor. The temple is dedicated to Lord Shiva (Siddeshwara Swamy) and is situated amidst unique rock formations and hillocks that extend for nearly 2 kilometers.

According to local tradition, the hill was a place of meditation for the Navanathas (nine sages), giving rise to the name Navanathapura. The temple complex includes several shrines such as Shivalayam, Ramalayam, Hanuman Temple, and Durga Devi Temple. Many of these are believed to be self-manifested (Swayambhu) temples.

One of the major attractions is the ancient cave temple containing a Swayambhu Shiva Lingam. Devotees pass through a narrow cave entrance to reach the sanctum, creating a unique spiritual experience. A sacred temple tank known as Jeeva Koneru is also located near the temple.