The main block and facade of the British Museum, 
Bloomsbury (1823–46).
This is Smirke's largest and best known building.
In 1820, in his role as architect to the Office of Works, Smirke was invited to redesign the museum, although the complete design dates from 1823, and was for a building surrounding a large central courtyard with a grand south front, given the limited funds the work was divided into phases.
It is built of brick with the visible facades cased in Portland stone.
The first part to be constructed was the "King's Library" of 1823–1828, which forms the east wing.
The north section of the west wing, the "Egyptian Galleries" followed 1825–1834.
The north wing, housing the library and reading rooms, was built in 1833–1838.
The west wing and south front were built in 1842–1846.

The main feature of the south front is the great colonnade of 44 Greek Ionic columns.
The columns are 45 feet high and five feet in diameter; their capitals are loosely based on those of the temple of Athena Polias at Priene and the bases on those of the temple of Dionysus at Teos.
At the centre of the colonnade is an octastyle portico, two columns deep; the colonnade continues for three more columns before embracing the two wings to either side.
Beyond the facade Smirke built two smaller wings, with 
Doric pilasters, containing houses, the western one for the Director of the museum.
The major surviving interiors are the entrance hall with the Great Stair – in the form of an Imperial staircase– rising to the west, and the "King's Library".
This, built to house 65,000 books, is 300 feet long, 41 feet wide and 31 feet high, the centre section being slightly wider, with four great granite Corinthian columns.
The only major interior to survive in the north wing is the "Arched Room" at the west end.
The "Egyptian Gallery" matches the "King's Library" but is much plainer in decoration.
The main block and facade of the British Museum, 
Bloomsbury (1823–46). This is Smirke's largest and best known building. In 1820, in his role as architect to the Office of Works, Smirke was invited to redesign the museum, although the complete design dates from 1823, and was for a building surrounding a large central courtyard with a grand south front, given the limited funds the work was divided into phases. It is built of brick with the visible facades cased in Portland stone. The first part to be constructed was the "King's Library" of 1823–1828, which forms the east wing. The north section of the west wing, the "Egyptian Galleries" followed 1825–1834. The north wing, housing the library and reading rooms, was built in 1833–1838. The west wing and south front were built in 1842–1846.
The main feature of the south front is the great colonnade of 44 Greek Ionic columns. The columns are 45 feet high and five feet in diameter; their capitals are loosely based on those of the temple of Athena Polias at Priene and the bases on those of the temple of Dionysus at Teos. At the centre of the colonnade is an octastyle portico, two columns deep; the colonnade continues for three more columns before embracing the two wings to either side. Beyond the facade Smirke built two smaller wings, with 
Doric pilasters, containing houses, the western one for the Director of the museum. The major surviving interiors are the entrance hall with the Great Stair – in the form of an Imperial staircase– rising to the west, and the "King's Library". This, built to house 65,000 books, is 300 feet long, 41 feet wide and 31 feet high, the centre section being slightly wider, with four great granite Corinthian columns. The only major interior to survive in the north wing is the "Arched Room" at the west end. The "Egyptian Gallery" matches the "King's Library" but is much plainer in decoration.
Robert Smirke (architect)