The tributes have grown since the Duke of Cambridge and Prince Harry visited the site at Kensington Palace on Wednesday to see for themselves the outpouring of love and admiration for their mother.
A large floral display spelling out Diana's name is now the centrepiece of the hundreds of cards, flowers, pictures and candles marking the 20th anniversary of her death.
Hundreds of well-wishers have been flocking to the palace's gates and, just like William and Harry, have stopped to look at the photographs of the Princess and read the poignant messages.
Self-confessed Diana superfan John Loughrey began assembling the tributes a number of days ago along with others, and in the early hours of the morning lit a candle at the time Diana was said to have died following a car crash in Paris.
Mr Loughrey, who also took a large cake decorated with Diana's image to the gates, said: "As Prince William has said, we must keep her memory alive.
"I was very, very touched when Prince William and Prince Harry came to the golden gates and looked at the tributes and pointed at the pictures and pointed at the banner."
The 20th anniversary of Diana's death has attracted broadcasters from across the globe who have been interviewing the Princess's fans and making live reports with the gates as a backdrop.
Mr Loughrey added: "I've been coming here for 20 years. Diana was a very special woman; when she came on the scene in 1980 I knew she was special.
"You could put her in a room, you could be a bad mood, she would turn on like a light switch and she'd bring sunshine to everyone and you'd light up.
"Her legacy she's left behind is without a doubt her two sons, and she's left it to them to continue her good works."