Kate Middleton
Kate Middleton's trip to Grimsby delayed by thick fog (Reuters)

Kate Middleton's trip to Grimsby has been delayed by approximately an hour and a half due to thick fog.

The Duchess of Cambridge was travelling to the Lincolnshire seaport by helicopter from London but her arrival has been pushed back .

Her first point of call will be the National Fishing Heritage Centre at Alexandra Dock.

She will be given a guided tour of the museum by a local trawlerman. She will also hear about Grimsby's maritime and fishing heritage and discuss environmental issues surrounding fishing in the North Sea.

Grimsby was known as the largest fishing port in the world until the 1960s, when it began to decline because of the Cod Wars with Iceland.

After the museum, Kate will visit Humberside Fire and Rescue Service, where she will meet young people involved in a development course run by the Prince's Trust, as well as fire crews working at the station.

She will end her visit by officially opening the Havelock Academy, where she will have a tour of the school and meet A-level photography students.

Five months pregnant

Crowds of people have begun to gather in the town. Sarell Worley took her three children to see the Duchess at the Heritage Centre and told the Grimsby Telegraph: "Kate is a really good role model so I thought it would be good for the children to see.

"It's a great opportunity for my children to see the future queen."

Her daughter Zara added: "I want to ask Kate what is it like to live in Buckingham Palace."

The Duchess' last public appearance was in February, when she visited Action on Addiction's south London centre for women.

During the trip, Kate, who is five months pregnant, said she was nervous about giving birth as she spoke to a group of women recovering from drink and drug addictions.

She spoke to a woman called Natalie, who is expecting her second baby at about the same time as the Duchess.

"We're due about the same time. She's been unwell and feeling better now and I felt pretty much the same the first time," Natalie said.