English: Parasurameswara Swamy temple consists of several shrines with the main temple sanctum featuring one of the oldest known Shiva linga, variously dated between 3rd century BCE to 5th-century CE, with most scholars placing it between 2nd century BCE to 1st century CE. It is about 1.5 meter high, with an image of Shiva (Rudra) carved on the shaft, standing over a demon (sura). The back of the linga is faceted (half-hexagon).

The main shrine is apsidal in design, likely because apsidal designs were some of earliest forms of Hindu temples (see HR Ray, The Apsidal Shrine in Early Hinduism: Origins, Cultic Affiliation, World Archaeology, Vol. 36, No. 3, The Archaeology of Hinduism (Sep., 2004), pp. 343-359), . The Parasurameswara Swamy temple shows evidence of addition, restorations and expansion over time. Excavations suggest that the earliest version of the temple was also apsidal and was replaced with more lasting material as building methods and materials of construction improved. The inner structures of the current temple retain an apsidal form and are likely from 7th to 9th-century. The apsidal form, mandapa and walkways of the Gudimallam temple are similar to those found in Aihole region in northern Karnataka. The passageway inside the temple is from 11th to 12th century, while the outer mandapa is from the Vijayanagara empire era.

Outside the main sanctum, niches include statues of Shakti, Vishnu and others. These are cast bronze and from later centuries than the Shiva linga.

The walls of the Gudimallam temple show many inscriptions in different scripts, supporting the theory that the temple had many patrons over the centuries.

Outside the main shrine are smaller shrines dedicated to Surya and other Vedic deities.