Castle Bridge

From here to the Bock rock is only a few dozen metres, but the fortress engineers built a small masterpiece to cross them. The Castle Bridge went up in 1735, in the Austrian years, the work of the Kintzelé brothers, master builders from Bridel, in red Luxembourg sandstone. What makes it odd is that it gives you four ways across: the road over the top; a walkway through the small arches beneath it; a spiral staircase climbing up inside the main arch; and a tunnel under the road at the very bottom, which joined the casemates of the Bock to those under the old town. A garrison could move men, guns and powder between the two without anyone in the valley seeing a thing. Through the main arch runs the road down to the Grund, the Rue Sosthène Weis.

The bridge you're standing on, though, is a copy. The original stood almost untouched for two centuries, was widened once in 1933, and in 1993 was demolished outright and rebuilt to the old plans, only wider, at 8.60 metres. Luxembourg's conservationists were furious: the minister responsible was handed the "Golden Excavator", the prize for the year's worst treatment of a historic building. Turner had painted this bridge and the rock behind it around 1839, when the city was still a fortress and the walls ran unbroken; the view is much the same, the stones are not.

Across the bridge, on the rock, the jagged stump of a tower is the Hollow Tooth — the Huelen Zant. Nearly everyone takes it for the last remains of Count Siegfried's castle of 963. It isn't. It's the left-hand tower of the fortress's second gate, and when the citadel on the Bock was pulled down in 1874 the state architect, Charles Arendt, deliberately reshaped it into a ruin and left it standing, because a ruin on a rock was what a romantic age wanted to see. The castle's real story is told at the casemates; this is a nineteenth-century piece of stagecraft, and none the worse for it.