The 68-year-old is raising funds in memory of his late brother Martin, who had Down's Syndrome. Mallett set off from Paddington Station in London last year, making his way around the coast of Britain.
Over five thousand miles later, he made it to Northern Ireland for the latest leg of his pedal-powered pilgrimage.
Mallett rose to fame in the 1980s, presenting popular children's programmes such as Wide Awake Club, which later became known as Wacaday, and Around the World in 80 Seconds.
In recent days he has visited Limavady, Coleraine, Portstewart, Portrush, Dunluce Castle and Portballintrae – and is obviously loving the north coast!
Here’s a few of his adventures...
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A talented artist, Timmy took time to paint this picture of Dunluce Castle. Photo: TIMMY MALLETT
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TV presenter Timmy Mallett is cycling around the UK and Ireland and has reached the Causeway Coast. Here he met with the Mayor and Deputy Mayor of Causeway Coast and Glens Borough Council, Steven Callaghan and Margaret Anne McKillop. Photo: TIMMY MALLETT
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TV presenter Timmy Mallett is cycling around the UK and Ireland and has reached the Causeway Coast. Photo: TIMMY MALLETT
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TV presenter Timmy Mallett is cycling around the UK and Ireland and has reached the Causeway Coast. Photo: TIMMY MALLETT