I think you need to be careful about too much exposition in one go here. Some of it can probably be integrated into the rest of the paragraph/scene and it’ll read as being a little less information-heavy.
I’d probably get rid of the "Since the founding" section of the sentence, and jump straight to "It remained locked"
I’m going to hazard a guess at this point in the chapter that The Emberheart is going to be pivotal to this story as a whole, so make it the absolute focus of this section.