The royal initials "Chon Por Ror" and "Sor Por" inscribed on the massive cliff at Pha Sadet are invaluable historical artifacts personally carved by King Chulalongkorn and Queen Saovabha Phongsri during their royal visit in 1895. These inscriptions serve as a monument to the success and immense perseverance required to construct the railway through complex mountain ranges, which at the time was plagued by both geographic obstacles and tropical diseases. Today, these clearly preserved engravings stand as a symbol of royal grace and a spiritual center for devotees and tourists to reflect on their legacy amidst the solemn and scenic backdrop of the historical railway tracks.