Hierapolis, A citie of Asia, ouer against Laodicea, where were certaine bathes, the water whereof would soone harden and congeale into the stone called Tophus. There is also a certaine caue in the earth, into whych if any liuing creature do enter, immediately it dyeth. Befure the mouth of it is a little valley of halfe an akers compasse, so darke, that scantlye the grounde may bee seene. Strabo writeth, that for experience he did let into this caue certaine sparrowes, whyehe forthwith did fall downe dead. Aboute that citie also is a water that dieth wooll of a purple colour.
Lewis and Short: Latin dictionary
Hĭĕrāpŏlis, is, f., = *(iera/polis. I.A city of Great Phrygia, now Pambouk Kaleh, Vitr. 8, 3, 10; Plin. 2, 93, 95, 208; Vulg. Col. 4, 13.—Hence, 1. Hĭĕrāpŏ-lītae, ārum, m., the inhabitants of Hierapolis, Plin. 5, 29, 29, 105.—2. Hĭĕrā-pŏlītāni, ōrum, m., the same, Macr. S. 1, 7; Dig. 43, 20, 1.