People stand by the Roman aqueduct in Segovia, Spain, Aug. 6, 2018. Segovia is famous for its Roman aqueduct, as well as ancient churches and castles. The city center of Segovia was declared World Heritage by the UNESCO in 1985. (Xinhua/Guo Qiuda)

A man walks his dogs on a street in Segovia, Spain, Aug. 5, 2018. Segovia is famous for its Roman aqueduct, as well as ancient churches and castles. The city center of Segovia was declared World Heritage by the UNESCO in 1985. (Xinhua/Guo Qiuda)

People walk on a street in Segovia, Spain, Aug. 5, 2018. Segovia is famous for its Roman aqueduct, as well as ancient churches and castles. The city center of Segovia was declared World Heritage by the UNESCO in 1985. (Xinhua/Guo Qiuda)

A man and his daughter rest on a street in Segovia, Spain, Aug. 5, 2018. Segovia is famous for its Roman aqueduct, as well as ancient churches and castles. The city center of Segovia was declared World Heritage by the UNESCO in 1985. (Xinhua/Guo Qiuda)

A man walks by the Roman aqueduct in Segovia, Spain, Aug. 6, 2018. Segovia is famous for its Roman aqueduct, as well as ancient churches and castles. The city center of Segovia was declared World Heritage by the UNESCO in 1985. (Xinhua/Guo Qiuda)

A woman walks by the Roman aqueduct in Segovia, Spain, Aug. 6, 2018. Segovia is famous for its Roman aqueduct, as well as ancient churches and castles. The city center of Segovia was declared World Heritage by the UNESCO in 1985. (Xinhua/Guo Qiuda)

Photo taken on Aug. 6, 2018 shows the Segovia Fortress in Segovia, Spain. Segovia is famous for its Roman aqueduct, as well as ancient churches and castles. The city center of Segovia was declared World Heritage by the UNESCO in 1985. (Xinhua/Guo Qiuda)