The Rotunda is a part of the Grade II* listed Battleship Building on the Harrow Road beside the elevated A40 and the Paddington Arm of the Grand Union canal. It was designed in the mid-1960s by architect Paul Hamilton and built in 1969 as a road vehicle maintenance depot for British Rail. The 1994 listing describes it as 'PADDINGTON BRITISH RAIL MAINTENANCE DEPOT, EAST BLOCK, 179 HARROW RD'.
 
The building was converted into offices in 2000 and became Nissan Design Europe. It was abandoned by British Rail in the early 1980s (probably by the time I took this picture) and was derelict and covered in graffiti when they decided to move in. The photographs on their site show how the building interior has been splendidly redesigned accentuating its characteristics, and resembling the interior of some spacious spacecraft.
 
The Westway, the elevated section of the A40 was built between 1964-70 and opened as the A40(M), but lost its motorway status in 2000 when it was transferred to the Greater London Authority. The longest concrete structure in Britain when built, it devastated the north of Notting Hill, with homes and streets being demolished.
 
It was planned to be a link to the inner ring of the London Motorway Box, but the problems caused by its construction (and its cost) played an important role in the growth of opposition to these immensely disruptive roads which led to the abandonment of the Ringway scheme in 1973.
 
Campaigning against the devastation of the area led to 23 acres below the Westway being dedicated to community use, though the organisation set up to administer this has lost any roots it had in the community and lost its trust with commercial developments. You can read more about this at the Westway23 web site.