For more than 70 years, British broadcaster and naturalist, Sir David Attenborough has brought nature to our screens.At 100, he reflects on one unforgettable moment - coming face to face with mountain gorillas in Rwanda.Here’s that encounter from 1979.

It's Sir David Attenborough's 100th birthday and in 1980 he faced questions from an audience of young viewers about his life and television career. Lesley Judd hosted the show, and Attenborough talked about making a connection with gorillas, and his concerns for the environment.