Yangtze Delta, China

This scene is an original illustration set in Yangtze Delta, China. It lies in the subtropics, where the climate is humid subtropical — hot summers, no dry season.

A high semicircular stone arch bridge stands over a still canal, its reflection completing a full circle. White lime-washed houses with dark grey tiled roofs line both banks, their lower walls stained by damp. Mist hangs over the water, and the light is flat and shadowless.

Why are canal bridges built as a full semicircle?

The full-circle reflection is not decoration — a high arch lets loaded boats pass beneath without a drawbridge, and the semicircle is the cheapest span in compression. Houses fronting directly onto water mean the canal is the street. Persistent mist under a fully overcast early summer sky belongs to a warm humid delta during its long rainy season.

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