DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )

DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )

DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )

DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )

DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )

DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )

DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )

DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )

DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )

DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )

DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )

DENIZLI, TURKEY - JULY 27: Tourists spend their times at the travertine pools at the Pamukkale of Denizli Province in southwestern of Turkey on July 27, 2017. The city contains hot springs and travertines, terraces of carbonate minerals left by the flowing water. The ancient Greco-Roman and Byzantine city of Hierapolis was built on top of it. ( Mahmut Serdar Alakuş - Anadolu Agency )