British adventurer Karl Bushby said he was "absolutely overwhelmed" by the crowds who lined the Humber Bridge as he crossed it through thick mist on the final leg of his 31,000-mile (49,890 km) trek from South America to Hull.

Bushby left Chile in 1998 with the aim of walking home to the UK under two self-imposed rules: that he would not return until the journey was complete, and that he would not use transport to advance. Aged 29 at the time, he set out from Punta Arenas with a few hundred dollars in his pocket and turned north for home. By the time he swam back across the English Channel on 5 October, the former paratrooper, now 57, had crossed four continents as well as a frozen sea, deserts, mountains and jungles.

Speaking to BBC Radio Humberside on Sunday, he said: "[I'm] just absolutely overwhelmed. And we're not even home yet." The "we" may have referred to himself and The Beast, the cart he has spent 28 years pushing and which he described as "my Wilson", a reference to the volleyball that Tom Hanks's character talks to in the film Cast Away. "I'm just a homeless guy pushing a shopping trolley, and the next thing you know is this," he said, nodding to the crowds on the bridge. "And I have to really kind of just stop and think about what this means to other people."

The Humber Bridge has particular significance for Bushby, who has said the opportunity to embark on the walk came after the breakdown of his marriage, when his wife returned to Northern Ireland with their son. Recalling an early walk south to test his first cart, he said he remembered none of that journey except the bridge. "There's that mystic look to it where you can't see the other side of the river," he said. "It's kind of almost symbolic. The Humber Bridge has always been that iconic landmark in my mind."

Bushby is due to complete the challenge on Monday, when he will be met by his mother, his son and his granddaughter on arrival in Hull. He will begin the final part of the walk back to his mother's home in north Hull, setting off from Hessle and walking to Queen Victoria Square, where a reception will be held for him outside the Civic Hall.

Sources: BBC News UK.