The Hospital Postern provided cover from St. Martins Battery at Dover's Western Heights to the Military hospital at Aycliffe. That's what the book says anyway. I personally don't believe it; I nearly ended up in hospital trying to climb out!
1. In through the Bottom at the end of the west ditch.
2. Past the drawbridge workings.
3. Through the bottom doors. (looking back at them)
4. Up the stairs.
5. To the top entrance.
6. Looking back down.
7. Climb up the gate to get out.
8. The sealed top entrance.