Solution:The first rock-cut architecture of Mahendravarman I, known as the Laksitayatana Trimurti Temple, was built at Mandagapattu. This temple is significant as it marks the beginning of Pallava rockcut architecture. The temple inscription explicitly states that it was built without the use of bricks, timber, metal, or mortar, reflecting an architectural transition from structural temples to rock-cut temples. Mahendravarman I pioneered this style, which was further developed by his successors.