The Neretva River is a flowing emerald code in the Balkan Peninsula - it cuts through the chest of the karst landform, and uses the millennium turbulence to polish out the arc of the Mostar Old Bridge. On the riverbed, the stone foundation of the Ottoman Empire and the shells of the war years are sleeping. When divers jump into the cracks of time, the green water becomes a canvas, dyeing the 400-year-old bridge shadow, the mottled bullet-hole walls on both sides, and the silhouette of the monastery on the cliff into a dynamic historical scroll. The river water not only hides the ingenuity of geological movement, but also surges with the alternating pulse of war and peace. Every ripple tells us: nature and civilization have always coexisted in each other's reflection.