The emperor Hadrian built an enormous theatre in the city, made to seat 15,000 people.
(Source: whitman.edu/theatre/theatr…)
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Source: perseus.tufts.edu/hopper/text?do…
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But recent excavations have shown that the temple’s deadly effects were very real.
(Bill McKelvie 500px.com/photo/10403083…)
![](https://pbs.twimg.com/media/Diic-1AWsAEaah-.jpg)
Normal atmospheric levels of CO₂ are around 0.039%, and 10% is enough to asphyxiate a person in 30 minutes.
(Pfanz et al. link.springer.com/article/10.100…)
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“They hold their breath as much as they can," Strabo tells us. “I could see in their countenances a kind of suffocating attack”
Source: perseus.tufts.edu/hopper/text?do…
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While the modern archaeologists uncovered the site, they observed birds flying near to the cave mouth and dropping dead from the noxious vapours.
(Pfanz et al. link.springer.com/article/10.100…)
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(Pfanz, History of Toxicology and Environmental Health books.google.co.uk/books?id=igrUA…)
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In the 6th century CE, the Ploutonion’s entrance was bricked up, & the temple was vandalised. Earthquakes in later centuries took care of the rest.
(📷Carole Raddato @carolemadge)
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Pfanz et al, "Deadly CO2 gases in the Plutonium of Hierapolis": link.springer.com/article/10.100…
Pfanz, The Ancient Gates to Hell: books.google.co.uk/books?id=igrUA…
Şimşek, Landscape and History in the Lykos Valley: books.google.co.uk/books?id=T2XXD…
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