FINALLY THEY TRAVELED to the rounded top of a mountain where an old stone tower stood, flanked by schlock-heaps instead of bastions. A half-wit could see that the Doctor had been at work here. Rising from the top of the tower was a curious windmill, spinning round sideways like a top instead of rolling like a wheel, so that it didn't have to turn its face into the wind. The base of the tower was protected by an old-fashioned stone curtain-wall that had been repaired recently (they were afraid of being attacked by people who, however, did not have modern artillery). Likewise the gate was new, and it was bolted. A musket-toting engineer opened it for them as soon as the Doctor announced himself, and wasted no time bolting it behind them.