Benson, Sir John (1812–74), architect and engineer, was the only son of John Benson of Collooney, Co. Sligo. He probably trained at the Dublin Society school of architectural drawing, and won premiums in 1832. His commissions in Co. Sligo included restoration work on Markree Castle, Collooney; several churches, including the Gothic-revival Church of the Assumption, Collooney (1843–78); and Victoria Bridge, Sligo.
Appointed county surveyor for the west riding of Cork (1846) and transferred immediately to the east riding, he superintended famine relief works, constructing several hundred miles of road. Promoted surveyor of the county and city of Cork (1851–73) and engineer for the harbour and port of Cork, he built many bridges, including St Patrick's Bridge (1859–61) and North Gate Bridge, notable for the beauty of their design; Benson Bridge was named after him. He designed Cork waterworks, piers, and quays, including the deep-water Victoria Quay, which, with improved dredging of the river, enabled the largest ships to dock, doubling Cork harbour revenues. He was engineer to the Rathkeale & Newcastle and Cork & Limerick railways, director of the Cork & Kinsale, and engineer-in-chief and architect to the Cork & Passage Junction; he designed the Penrose Marsh terminus for the Great Southern & Western, with its impressive Doric colonnade (completed 1860; subsequently demolished).
In Cork he designed the markets, including the rebuilt butter market (c.1852), the Athenæum, Camden Quay (begun c.1854), and several churches, notably the Gothic-revival church of St Vincent de Paul, Sunday's Well (1851–7). He is most famous for his design in timber, iron, and glass for the industrial exhibition, Dublin (1853); he was knighted on the opening day.
He published articles in the Transactions of the Institution of the Civil Engineers of Ireland; was a member of the RSAI (1856) and ICE (1862) and held office (including the vice-presidency, 1864–5) in the RIAI; and as a freemason was provincial grand architect and master (1850) of Lodge 1, Cork, where he resided. He married (1849) Mary Clementine Pyne; they had no children. Benson had a pleasant disposition and was highly respected. He went to England for health reasons and was resident at Alexander Sq., Brompton, London, where he died 17 October 1874.