Luxembourg is set dramatically on a high bluff over the river. There are several extraordinary stone viaducts that carry roads and railroads up to the city. I believe that one of them is visible (from above) on the left side of the photograph.
When the bluff filled up, further development was centered on another bluff across the ravine. The two parts of the city gaze across the ravine at one another. A lovely park has been built in the ravine. It is important to be aware of flood hazards in siting cities, and it makes very good sense to put the inhabited areas up high, leaving the parks in the lower reaches, where there is often water to be enjoyed. This protects the buildings form flooding while making good use of the flood plain. Cities that ignore this pattern have done so at their peril.
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