Underwater Clock Tower

Here is another underwater place that I really like. The clock tower, it had a lot of records, mostly magical, so the water didn't hurt them. There were patrols, ponies made sure that no one crossed the border of Equestria. And, believe it or not, Celestia and Luna were already at that time, although it is quite well a long time ago. How old are these princesses anyway?...There are also hammerhead sharks, but since my talent is to adjure sharks, they do not harm me.