London Heathrow Airport (LHR) does not have a total 24-hour ban on flights, but it operates under a very strict night flight curfew to protect the millions of residents in surrounding densely populated neighborhoods. Generally, there are no scheduled departures between 10:50 PM and 6:00 AM, and no scheduled arrivals between 10:55 PM and 4:50 AM. The most restrictive period, known as the "Night Quota Period," runs from 11:30 PM to 6:00 AM. During this time, the government limits the airport to only 5,800 movements per year, which are mostly reserved for delayed flights or emergency landings. Most of the night traffic consists of "early morning arrivals" from Asia and South Africa that land after 4:30 AM. If a flight is delayed and misses the 11:30 PM cut-off, it is often "curfewed" and forced to stay overnight, with the airline providing hotel vouchers for passengers. This strict regulation makes Heathrow one of the quietest major hubs in Europe during the late-night hours, balancing global connectivity with local public health.