The weather in September is normally warm as London enjoys the last few weeks of summer. This is one of the liveliest months in London, with a host of festivals, activities and special events to suit all interests, from boating to architecture.
For the first time this year, Totally Thames features a month-long celebration of the river, with 30 days of river-based events from the Falmouth to Royal Greenwich Tall Ships Festival to music, art and illuminations. This inaugural festival replaces the annual 10-day Mayor's Thames Festival.
Also part of the festival this year is the Great River Race, a colourful spectacle where more than 300 vessels (with oars or paddles) traverse a 21-mile (34km) route past some of London's most iconic landmarks.
Back on dry land, more than 700 of the capital's most unusual, awesome and interesting buildings open their doors to the public at Open House London.
Another city-wide event, the London Design Festival, presents exhibitions, installations, talks, seminars and parties at various venues.
In the City of London, the Pearly Kings and Queens Harvest Festival is part of London's rich heritage and includes a glittering parade through the streets.
WEATHER: For average seasonal temperatures and rainfall, see our London Weather page.
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