The Pallavas were a dynasty that ruled in South India during the 4th to 9th centuries CE. They had their capital at Kanchipuram, which is located in present-day Tamil Nadu. Kanchipuram was an important city during the Pallava reign and served as the political and cultural center of their empire.

Option 1: Kanchipuram - This is the correct answer. Kanchipuram was the capital city of the Pallavas and the seat of their power.

Option 2: Madurai - Although Madurai is a significant city in Tamil Nadu, it was not the capital of the Pallavas. Madurai was the capital of the Pandya dynasty.

Option 3: Tanjore - Tanjore, also known as Thanjavur, was not the capital of the Pallavas. It was the capital of the Chola dynasty.

Option 4: Tiruchendur - Tiruchendur is a temple town in Tamil Nadu but was not the capital or a significant center of the Pallavas.

In summary, the Pallavas ruled from Kanchipuram, which was their capital city.