The year 1800 in architecture involved some significant events.

Buildings and structures

Buildings

• June 30 – Replacement Teatro Riccardi opera house in Bergamo, Lombardy, designed by Giovanni Francesco Lucchini, is opened.
• November 1 – The White House in Washington D.C., United States, is completed. However, the porticoes are not added until 1825.^[1]
• The King's Inns in Dublin, designed by James Gandon, are completed.
• Santiago Metropolitan Cathedral in Chile is completed.
• East Cowes Castle on the Isle of Wight, designed by John Nash for his own use, is completed.
• Tyringham Hall near Newport Pagnell in England, designed by John Soane, is completed.
• Gosford House in East Lothian, Scotland, is completed to the 1790 design of Robert Adam (died 1792).

Publications

• Birch's Views of Philadelphia published.

Awards

• Grand Prix de Rome, architecture: Simon Vallot and Jean-François-Julien Mesnager.

Births

• February 27 – Robert Willis, English mechanical engineer, phonetician and architectural historian (died 1875)
• August 17 – Isaiah Rogers, American architect (died 1869)
• September 30 – Decimus Burton, English architect (died 1881)
• December 4 – Louis Dupasquier [fr], French architect (died 1870)

Deaths

• May 21 – Carl August Ehrensvärd, Swedish naval officer, painter, author and neoclassical architect (born 1745)

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