Kebar Dam is an exceptionally early masonry arch dam, generally dated to around 1300. Its small reservoir is no longer used and is mostly filled with silt, making it a rare example of a very old dam that still stands but has effectively lost its original function. ([en.wikipedia.org](https://en.wikipedia.org/wiki/Kebar_Dam)) - **Unusual technique:** early arch-dam design in masonry, often cited as one of the oldest surviving examples of that structural idea. ([iranicaonline.org](https://www.iranicaonline.org/articles/band-dam/?utm_source=openai)) - **Why it remains:** chiefly for historical and engineering significance. ([en.wikipedia.org](https://en.wikipedia.org/wiki/Kebar_Dam)) - **Further information:** - https://www.iranicaonline.org/articles/band-dam/

Kebar River near Qom, Qom Province, Iran