Historians reconstructed the ancient city's original appearance based on archaeological findings.

reconstructed 是动词 reconstruct 的过去式形式。reconstruct 由前缀 re-（表示"重新"）和 construct（建造）组成，字面意思是"重新建造"，引申为"重建、复原"。在句中指根据现有证据还原古代城市原本的样子。