What Is the Modern London Bridge Made Of? Concrete, Steel, and Granite

The current London Bridge—completed in 1973—is a thoroughly modern structure, worlds apart from its medieval predecessor of nursery-rhyme fame. Its materials reflect 20th-century engineering:

• Reinforced Concrete: The primary structural material for piers, abutments, and the box-girder deck. High compressive strength, durability, and moldability for the clean, functional lines.
• Steel: Used for reinforcement within the concrete (rebar), and critically, for the bascules (the movable leaves that can be raised for tall vessels—though rarely used today). Steel's high tensile strength handles the dynamic loads of opening/closing.
• Granite Cladding: The exterior faces are faced with granite—an igneous rock prized for weathering resistance, low maintenance, and aesthetic gravitas. It nods to the stone bridges of the past while shielding the concrete core.

Why Not Stone Throughout?

A solid masonry arch bridge of this span (928 ft / 283 m) would be impossibly massive, expensive, and slow to build. The concrete box girder achieves the same span with a fraction of the weight and material, using post-tensioning to handle tension forces that stone cannot.

The result: a bridge that looks appropriately stolid for its historic site, but performs like a modern highway structure—carrying 50,000+ vehicles daily over the Thames.