Twin Towers across the Thames

Twin Towers across the Thames is an original illustration set in Tower Bridge, London, United Kingdom. It lies in mid-latitudes, where the climate is oceanic — mild, wet through the year.

Two pale Gothic towers stand on river piers, joined by high walkways and pale blue steelwork. The central roadway sits low over the gray-green Thames, while suspension elements reach toward the banks and a small vessel passes below the closed span.

Why can the roadway between these two stone towers open above a tidal river?

A low road crossing served busy streets, but tall ships still needed access to the upstream docks, so the central roadway was built as two lifting bascules. High walkways and separate side spans preserve the distinctive stacked profile around the towers. That compromise between a tidal commercial river and dense urban traffic explains the form of London's Tower Bridge.

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