Al-Kharj, The Eastern Mosque in Al-Yamamah village, Al-Kharj governorate, is a remarkable witness of the enduring Najdi architectural style.According to historical sources, the mosque was constructed between 1050 and 1100 AH.The mosque's architectural style was crafted to suit the prevailing climatic conditions of the region. A basement was constructed to ensure warmth for worshippers and students during winter, and a cool place from the harsh summer heat. The mosque's roof, built using tamarisk wood, is flat and features a solid, level layer to create a surface that aligns with the mihrab (prayer niche) on the ground floor.Abdulaziz bin Ibrahim Al-Saees, an expert on local history, said that a room for ablution was constructed adjacent to the mosque, and a well was dug in the northwestern part of the mosque to provide water both for the mosque and for the local community.The mosque's basement features openings that allow natural light and air to filter in during the day and hangers for lamps to provi de illumination at night.The courtyard separates the basement area from the upper part of the mosque, and accommodates 40-60 worshippers.The old mosque was last used in 1432 AH, as it needed restoration. As a valuable historical landmark, it had to be revamped by experts. The locals kept the mosque in its original state, placing barriers around it for protection.According to historical documents, the mosque suffered severe damage in 1170 AH, but was subsequently restored. The mosque was constructed using materials sourced from the local environment, including solid, petrified mud veins and a layer of mud mixed with gypsum, a local material boiled to resemble natural gypsum, palm fronds, and twigs.The mosque was last restored approximately 70 years ago.Source: Saudi Press Agency