This is a memory envelope for the first Boeing 747 flight from London to Tokyo via Anchorage (USA). The airports are London Heathrow airport, Anchorage airport and Tokyo Haneda airport. The depart date is 3rd of April of 1974, the landing date is 4th of April of 1974.
This envelope has great history value. firstly, this envelope is good evidence to reveal the name of 'British Airway' was start from April of 1974 (picture 1). The italic words are from Wikipedia In 1972 the BOAC and BEA managements were combined under the newly formed British Airways Board, with the physical operations of the separate airlines coming together as British Airways on 1 April 1974. So, my envelope is a very good evidence to record this history. You will be very difficulty to find any document, printing 'British Airway', is earlier than this envelope as this envelope is the 3rd of April of 1974 (picture 1). This is the first value of the envelope.
The second value of this envelope is we can know that the Boeing 747. This is very clear evidence The first Boeing flight is operated by British Airway is 3rd of April of 1974 (picture 1)
The third value of this envelope is the envelope has clear arriving stamps (picture 2, 3)
The envelope is still in very good condition, no broken and clean.