More than 7,000 block dominoes toppled their way over a city-wide route to mark the start of the 250th Norfolk and Norwich Festival.
The installation, by artist Julian Maynard Smith, took more than 200 volunteers three days to put in place over a 1.6-mile (2.5km) course that snaked through the centre of Norwich. It tumbled, watched by thousands of people, in about 30 minutes on Friday evening.
The work, which has been replicated across cities of the world since 2009, grew out of an initial idea to connect boroughs of London.
He said the whole purpose of the performance was to make people look afresh at their environment.