A child psychiatrist who caught the last train out of Poland before the Nazis invaded has celebrated her 100th birthday.

Mary Burns, the great-granddaughter of the founder of Channing School in Highgate, marked the milestone by drinking champagne with four generations of her family on Thursday before a party at the Mary Feilding Guild residential home in North Hill, Highgate.

She was presented with a congratulatory message from the Queen after her granddaughter, TV and stage actress Ella Kenion, performed a selection of poems for dozens of her friends and fellow residents.

Mrs Burns, who has lived in Highgate nearly all her life, said: “My first memory is that I was taken out of my cot in Cardiff where we were living.

“I was wrapped in a blanket and taken out into the garden to be shown a German zeppelin. It was the First World War.”

She said the secret of her longevity was “fresh air, exercise and lots of green vegetables”.

A woman who has seen two world wars first-hand, Mrs Burns narrowly escaped the Nazis during a working holiday to Poland with a friend in August 1939.

On August 30, she ended her travels and left the country for Berlin on what turned out to be the last train to leave Poland’s capital Warsaw.

Two days later, 1.5million German troops descended on the country and Warsaw was razed to the ground.

Her 71-year-old son Sir Andrew Burns, the UK’s envoy for post-Holocaust issues, said: “She or I may not even be here if she hadn’t got out in time.”

Mrs Burns, who worked at the former Tetherdown Child Guidance Clinic in Muswell Hill for 30 years, attended Channing School before winning a scholarship to study medieval French at Oxford University.

She was a near-constant presence at the unitarian school even in her adult years as chairman of governors from 1969 until 1975 and a governor until 1985.

Mrs Burns, who has nine grandchildren and eight great-grandchildren, lived independently in Cromwell Avenue, Highgate, until the age of 96, when she moved into the Mary Feilding Guild because of her failing sight.

Her hobbies include listening to audio books of classical literature by Homer and Virgil.