Thailand - Phuphrabat Historical Park

"Designated as Phuphrabat Historical Park, the site is the landscape of a wooded sandstone hill adorned with patches of huge bare rocks in spectacular overhanging positions, some balanced on pedestals of oddity. This scenic and awesome beauty of nature has had, over the millennia since prehistoric times, a compelling spiritual effect on humans in the neighbourhood to associate the site with sanctity, as evidenced by the presence of visual arts of different cultural periods. The scenic Phuphrabat associative cultural landscape is unique in that this single site contains authentic cultural treasures that represent major cultures of different periods of the region, effectively epitomizing the continuum of the whole cultural history of mainland Southeast Asia. All together, the site incorporates separate 68 cultural locations, most of which contain rock paintings of the prehistoric period as well as the stylised, religious icons of the successive cultural periods.." 

Source; UNESCO World Heritage Tentative List

Bought this postcard while in Thailand and sent home with matching stamp. I was at Udon Thani near this site.