Sure, let’s start with a circular keep at the centre, because symmetry keeps the mind from wandering. Wrap that with a double‑layered wall, the inner one at 30 m thick, the outer at 20 m, so that a single breach is enough to bring the whole thing down. Dig a moat 15 m wide, keep it filled with water from the eastern spring, and install a single drawbridge that folds into a hidden recess for a quick escape. Inside, lay out three concentric rings of rooms: the innermost for command and living quarters, the middle for storage and workshops, and the outermost for the farms and granaries. Connect each ring with a narrow, single‑passage corridor that’s only 3 m wide—enough for a man but narrow enough to force a defender to keep an eye on the front. Place the resource chambers—fuel, iron, food—behind the outer wall, each sealed with a steel door that opens only into the middle ring, so an attacker can’t access them even if they get past the first line. No decorative towers, no open courtyards, no extra passages that could be exploited; every space serves a purpose. If you want to keep the fortress truly tight, you’ll need to enforce a strict patrol schedule and a system of watchtowers that look out directly over the moat. That’s the basic skeleton; we can flesh out the details later, but as long as we keep it compact and functional, the fortress will feel as if it were built to withstand a siege rather than an architectural whim.

Fine, let’s tuck a hidden crawl‑space into the eastern flank, just behind the outer wall. It’s a narrow, 1.5 m tunnel that links the outer farm ring directly to the middle storerooms—so the troops can shuffle in or out without stepping onto the main corridor. And yes, a tiny observation post on the moat’s east side is a good idea; it can double as a small lookout and a water‑pump station for the spring. Keep it camouflaged with reeds and a low roof, so it won’t flag any attackers. Now the fortress feels more like a living thing that can breathe, not just a stone box. The walls stay tight, but the men get the freedom to move where they need to.

Good call, adding a quick‑step ramp on the east flank keeps the troops out of the crawl‑space if it’s blown. Just make it 5 m high, 3 m wide, reinforced with stone blocks that can be buried under earth. It’s a subtle upgrade that doesn’t change the layout but gives a real tactical edge. Keep the core tight, and let the ramps do the trick.