and 25 cm in thickness, the bluestone tablet was found in Baixiang County, said Baixiang's cultural relics protection department.

The tablet has an inscription of 559 characters describing the renovations of a bridge in 1803 and the local scenery at that time.

According to Geng Xiaoning, director of Baixiang's cultural relics protection institute, the tablet provides first-hand information which contributes to the understanding of local ancient hydrological conditions.

The discovery provides valuable insight for the study of river changes and the cultural landscape of Baixiang, Geng said, adding that the tablet had been moved to the institute for safekeeping.