Tower Bridge Design: Gothic Skin, Industrial Skeleton

Anatomy of an Icon

Tower Bridge (1886–1894) is a bascule + suspension hybrid:

Two Towers: 65 m (213 ft) high; steel frame clad in Portland stone & Cornish granite (Gothic Revival).
Central Span: 61 m (200 ft) between towers; two bascules (leaves), 1,200 tonnes each.
Bascule Mechanism: Original hydraulic (steam → oil → electric), raises 83° in 90 sec. Counterweights in piers.
Suspension Spans: 82 m (270 ft) each side; chains anchor to abutments.
High-Level Walkways: 43 m (141 ft) long, 44 m (144 ft) above river. Originally for pedestrians during lifts; now exhibition + glass floor.
Roadway: 100 m (328 ft) total between abutments.

11,000 tonnes steel, 70,000 tonnes concrete, 31M bricks, 22,000 litres paint (repainted 2008–10).

Sir Horace Jones (architect), Sir John Wolfe Barry (engineer). Jones died 1887; Barry completed.

Form follows function—then gets dressed for the coronation.

Metros & Subways