To retain, restore and revive the glorious history of the world, 18 April is marked as the World Heritage Day. The day seeks to create worldwide awareness on protecting important world monuments and historical sites. Here is a glimpse at some lesser known amazing historical sites and monuments listed in the World Heritage Sites.

Pavagadh Archaeological Park, located in the 16th century Hindu historical city of Champaner in Gujarat's Panchmahal district, was listed by UNESCO in 2004. Built by Sultan Mahmud Begada, the park beautifully documents the shift from Hindu to Muslim culture and architecture in the early 16th century. It houses palaces, mosques, tombs and temples, residential complexes, and agricultural structures dating back to the 8th-14th centuries. A religious park, it is highly praised by many visitors. 

Bhimbetka Rock Shelters: Located amid dense forest, it is a cluster of rock shelters. Discovered in 1957, it is truly an archaeological wonder. The site is said to be over 200,000 years old. It was added to the World Heritage list in 2003. Located in the foothills of Vindya Range in Madhya Pradesh, it is a "magnificent repository of rock paintings within natural rock shelters". It has traces of the stone age in the Indian Subcontinent. In fact, the traces of the first human life in the region can be seen here.. 

Mountain Railways: Set amid breathtaking beautiful green landscapes, Mountain Railways of India is a collective listing of the Darjeeling Himalayan Railway, the Nilgiri Mountain Railway and the Kalka-Shimla Railway, which added to the UNESCO's list in 1999, 2005 and 2008, respectively. They are a sight to behold and the train ride through the blue mountains and lush forest is a thrilling experience not to be missed.