I've saw in Well of Souls page (too bad it's edited), it is said that there's a building for City Center called 'Castle' in Alpha versions. seen as either a capitol building (Palace) for city states and appears to be buildable anywhere except the capitol city (where Palace always is). 1. What was its (intended) in game functions. Did it provides any training speeds or XPs for any units trained there? did it provides ranged attack once it's build? 2. And now it became only Technology, what and when did Firaxis decided to exclude it entirely? was it due to the inceptions of District concepts (and specifically) Encampments?