Pig Memorial was built in 1913, the year of Queen Saovabha Phongsri's 50th Birthday Anniversary.
Its official name is "Sahachart Memorial" (อนุสาวรีย์สหชาติ), which refers to "The Memorial of Those Who Were Born in The Same Year", which were Prince Narisara Nuvadtivongs, Phraya Phiphat Kosa (Celestino Xavier), and Phraya Ratcha Songkhram (Kon Hongsakul), all of the three had jointly built the memorial as a gesture of gratitude to the queen.
The pig sculpture of the memorial is made of gilded cast metal.
Initially, the sculpture was resting on large stone pillars, which have since been replaced by a higher, mountain-shaped concrete base.
Its structure is cemented adjacent to the memorial, which is located in the west of the bridge.