Mamallapuram, also known as Mahabalipuram is a town in Kancheepuram. It is around 60 km south from the city of Chennai. It is an ancient historic town and was a bustling sea-port during the time of Periplus (1st century CE) and Ptolemy (140 CE). By the 7th Century it was a Port city of South Indian dynasty of the Pallavas. It has various historic monuments built largely between the 7th and the 9th centuries, and has been classified as a UNESCO World Heritage Site. Famous Shore temple is a structural temple, built in 700 - 728 AD, with blocks of granite, dating from the 8th century AD. It was built on a promontory sticking out into the Bay of Bengal at Mahabalipuram. The Shore Temple is so named because it overlooks the shore of the Bay of Bengal. The cancellation depicts Shore temple of Mahabalipuram.
(Note: It appears that four different cancellations are used at different period for Mamallapuram / Mahabalipuram)