Notwithstanding what's printed at the top of this postcard, this is a photograph of the Porte Stanislaus in Nancy. It is seen from the other side in the "Gate Closing a Vista" chapter. From this vantage, however, the gate serves more to frame a view than to create a sense of enclosure (although it also serves that purpose as well).
Its function as a frame for a view has been assisted in this case by the photographer's choice of location to set up his tripod, which places the distant spire right under the top of the arch. We see this often in photography without being aware of it - good spaces almost always have a "perfect" vantage point. It's the best place to stand. Photographers seek these places out almost instinctively. Good urban design includes making sure that such places are there to be found.
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