The story of Trinity Bridge is, in miniature, a story about continuity and destruction. The original bridge was torn down by Parliamentary forces during the English Civil War — a practical military decision, since bridges controlled movement and Parliamentary and Royalist forces were operating in close proximity throughout the region in the 1640s. Trinity College rebuilt the crossing between 1651 and 1652. For over a century this second bridge served students, fellows, and visitors crossing the River Cam's middle stream. When the current bridge was designed in 1764, the college chose not to waste the old materials. Portland stone and Ketton stone from the 1651 structure were incorporated into the new construction. Trinity Bridge is now the eleventh bridge overall across the Cam and the seventh over its middle stream through Cambridge.

James Essex was the Cambridge architect most closely associated with the university in the mid-18th century. He designed the bridge in 1764, and construction was completed in 1765. Essex was a meticulous craftsman with a deep interest in Gothic architecture; he documented medieval buildings across England and published observations on their construction techniques. The Trinity Bridge commission was one of his civic works — simpler than his more elaborate ecclesiastical projects, but built to last. The money came from the estate of Dr. Francis Hooper, who died in 1763. Hooper had been a Senior Fellow of Trinity College. His bequest paid for the bridge, and in return his family's coat of arms — a triple-turreted shield — was carved into the stone alongside the arms of Trinity College. Both heraldic panels remain in place today.

Trinity Bridge is not just a crossing but part of a designed route. The bridge connects to the Avenue — a tree-lined path that runs from the main college buildings across Queen's Road and into the Trinity College Fellows' Garden. The garden occupies ground on the far side of the road, separated from the college's main site by the traffic that now flows along Queen's Road. Without the bridge and the Avenue, fellows would have to navigate the road to reach their garden. The arrangement is typical of the way Cambridge colleges have managed the urban expansion of the city around them: by building private passages, gates, and bridges that maintain continuity of the college's world even as the public city presses in. Trinity Bridge is Grade I listed.

Walk across Trinity Bridge today and you are crossing a structure made partly of materials that have been here since 1651. The triple arches that carry the road are a form that goes back to Roman bridge-building. The Portland and Ketton stone used here — Portland from Dorset, Ketton from Rutland — has been the material of English architecture for centuries: Portland stone also faces St Paul's Cathedral; Ketton stone built many of the Cambridge colleges. The bridge's modest proportions fit the scale of the river and the setting. This is not a monument designed to impress from a distance. It is functional, well-proportioned, and old. The coat of arms above it — of the college and of Francis Hooper, who died the year before the bridge was built — is a reminder that most buildings are built by someone, and funded by someone, and that both facts are worth recording.