Tumlu Castle is in a village that you can reach from Ceyhan by – very frequent – minibus (to Imamoğlu) in about twenty minutes. It sits on a rock outcrop and looks forbidding. It is, that is: I did not manage to get in. I found two spots where there was some sort of entrance, but both had such steep rocks on their doorstep that I did not dare to risk my neck and equipment, and after some trials gave up. So you can only see shots from the outside, and some of the surrounding countryside, shrouded in low clouds.
In 2022 I can add: On sites on the web it is suggested Tumlu Castle was used by Assyrian, Persian and Romans. But another, seemingly better informed site, calls it clearly Armenian in construction, i.e.: "It was probably built in one major building period at the end of the 12th century. In 1198 it was mentioned as being owned by a Rubenid called Thoros. Later Tumlu Castle was occupied by the Mamluks who carried out some substantial repairs. In 1375 the castle is said to be destroyed by the Mamluks." On that site one explains how, though entrance is free and open, they had to use ropes to get in.
TUMLU KALESİ
Tumlu Kalesi, Ceyhan’dan (İmamoğlu’na) çok sık kalkan minibüslerle yirmi dakikada ulaşabileceğiniz bir köyde bulunuyor. Bir kaya çıkıntısının üstünde duruyor ve ürkütücü görünüyor. Yani içine girmeyi başaramadım. Bir çeşit girişin bulunduğu iki ayrı nokta buldum, ama her ikisinin eşiğinde de o kadar dik kayalar vardı ki boynumu ve ekipmanlarımı riske atmaya cesaret edemedim ve biraz daha uğraştıktan sonra pes ettim. Bu yüzden sadece dışardan yaptığım çekimleri ve alçak bulutlarla örtülü kırsal çevreyi görebileceksiniz.

Türkçe çeviri: Melek Emir. Katkılarından dolayı teşekkür ederim.