A new blog post on the Final Fantasy XIV Lodestone has new information about upcoming instanced raid dungeons that will make their collective appearance in patch v1.18. The post lays out how long each raid takes, number of players and other information as well as the rewards gained for completion.
The Dzemael Darkhold
Formerly an expansive system of natural caverns, the Darkhold was established when Count Dzemael of Ishgard recognized its potential as a subterranean fortress in the war against dragonkind. Work has since been ongoing to prime its vaulted chambers and rocky passageways for military purposes. Recently, however, word has arrived by way of leaked intel that troops of foreign origin have seized occupation of the Darkhold for an as-yet unknown end.
Read more on the Final Fantasy XIV Lodestone.