ONE of Britain's most distinguished female engineers was the guest of honour at a school's speech day.

Joanna Kennedy OBE, a director of Ove Arup, whose projects have included the Sydney Opera House, King's Cross underground station and Durham's Kingsgate Bridge, attended the event at Durham High School for Girls.

She spoke about her work on sustainable buildings, including her research into why the Twin Towers collapsed - a topic close to Mrs Kennedy's heart, as she was in Manhattan on September 11, last year.