Kaviyoor is situated about 5 km east of Thiruvalla on the banks of the river Manimala. The places is of great archeological significance because of its rock cut cave temple known as Trikkukkudi Cave Temple carved on a huge rock. Dating back to the 8th century AD, this temple dedicated to Lord Siva bears close resemblance to the Pallava style of architecture. The stone engravings here are among the earliest specimens of stone sculpture in Kerala. The idol of the main deity, Lord Siva is represented in the form of 3 feet high Sivalinga and is enshrined in a square cave (sreekovil) of the temple. The shrine also contains idols of Ganapathy, Maharshi and Dwarapalakas. The Archaeological Department preserve this temple as a monument.