For thousands of years, bridges have been constructed to make transportation easier, thereby allowing cities and empires to flourish. But some bridges do more than just get you from point A to point B; instead, they marry form and function in unforgettable ways. Among the most iconic structures in the world, the best bridges rise to the level of art and become a permanent part of the landscape, seemingly encapsulating the local character. Each with a unique design and backstory.Connection between cities, ports, mines and neighboring civilizations brought the need of creating stable and permanent roads. For this purposes, many ancient civilizations started to leave their mark on history by leveling up uneven terrain, forging their way through wilderness and eventually, bridging rivers and extreme land formations with wood logs and stones.The engineers recognized that one of the most efficient ways to build a bridge was in an arch. Rather than stones or wood flat across a river, their bridges were built with an arching shape. Downward force from the top of an arch meets an equal force pushing up from the ground. As a result, each of the arch's sections are tightly squeezed, making the structure very rigid.Here's the list of 20 beautiful ancient bridges.