The Raj Bhavan in Kolkata, West Bengal, India.
Holy Cross Church, Boston, Massachusetts, designed by Charles Bulfinch, dedicated.
St. John's Chapel (New York City), designed by John McComb, Jr. and his brother Isaac.
Rivington Unitarian Chapel in Lancashire, England.
Bob Church, Cluj, Transylvania.
Casa del Labrador, designed by Isidro González Velásquez, at the Royal Palace of Aranjuez in Spain is completed.
Nantwich Bridge in Cheshire, England, built by William Lightfoot.
Grand Prix de Rome, architecture: François-Narcisse Pagot.
April 3 - David Bryce, Scottish architect (died 1876)
April 20 - Christian Hansen, Danish historicist architect (died 1883)
August 3 - Joseph Paxton, English gardener, architect and MP (died 1865)
October 16 - Robert Stephenson, English railway civil and mechanical engineer (died 1859)
November 29 - Gottfried Semper, German architect, art critic and professor of architecture (died 1879)
date unknown - Ottone Calderari, Italian architect and writer (born 1730)
1803 in architecture Wikipedia
The year 1803 in architecture involved some significant architectural events and new buildings.