If we needed castles again, how would they be built?

[Mosier]

@Bosda_Di_Chi_of_Tricor

If the attackers dig tunnels, & set large fires beneath your foundations, the uneven heating & colling could cause you some nasty problems.

In all cases, wall should be rounded–no sharp corners for siege machines to exploit.

Re–walls & infantry.

Imitate the wall system of Constantinople.
Walls of Constantinople - Wikipedia

On a smaller scale, of course.

Didn’t you hear what happened to the Theodosian Wall?

[Bosda_Di_Chi_of_Tricor]

@Mosier

Didn’t you hear what happened to the Theodosian Wall?

Yeah–they were damaged by an earthquake.

And withstood many, many attacks on the city.

[Moonlitherial]

Mainly underground.

You could have defensive towers and your wall protecting the inner courtyard where, relieved of the need for living space you could have a ground level living roof of crops.

[bump]

@Johnny_Bravo

I imagine that enough basement sub-levels with lots of steel and concrete reinforcement would stymie any medieval sapping attempts.

That was kind of what I was thinking as well- 75-100 foot deep massive reinforced concrete foundations; they could roll up and set fires on it all they want, but they’re not going to do much to 200 tons of reinforced concrete.