I've been playing 568 for quite some time.

Donghe Bridge, or Donghe Grand Bridge, was a modernized megabridge newly constructed by Qi Country this year. It was made of reinforced concrete, with its main components ordered from Tang Country, constituting a double-track railway bridge of considerable spectacle.

This great bridge spanned the Donghe River and served as the most vital transportation chokepoint in Qi Country as well as the gateway to the eastern side of the King City.

During its construction, to ensure the absolute safety of the bridge, defensive fortifications were built on both sides of the bridge, the most impressive of which were the four five-story bastions at each end.

The construction of such colossal bastion towers was in part for aesthetics and also had practical value.

These four massive bunkers could house troops tasked with guarding the bridge, maximizing the security of Donghe Bridge.