Hill, whose career in river cruising spanned more than two decades, was widely regarded as one of the industry's experts, earning admiration from colleagues and industry peers for his encyclopaedic knowledge, generous advice and unwavering enthusiasm for the sector.
Tributes have poured in from across the travel trade, with many describing Hill as a mentor, friend and one of the defining personalities of the river cruise community.
Phil Nuttall, Chief Executive of The Travel Village Group, described Hill as his "river cruise soul mate".
"I've said this before and I'll say it again. James was my river cruise soul mate… the original… the best… the legend," he said. "I'll forever cherish our time together sharing stories, theories and geography lessons at many airports, train station platform benches and of course on board the love of his life… a river boat. RIP my great friend… I’m gonna miss ya pal."
Retired travel agent Ian Warren, who affectionately nicknamed Hill "Old Man River", said he had always been willing to help fellow agents.
"Back in 2008 when I was thinking of purchasing a GoCruise franchise, he was one of the people I spoke to on a few occasions, and he was very helpful to me," Warren said. "Even after starting the franchise he was never too busy to help, and his knowledge was invaluable when I decided to specialise in Nile cruises."
He added: "He will be sorely missed by colleagues, suppliers and customers, and the river cruise industry will be a poorer place without him."
Helen Malan, a specialist at Cruise Holidays UK, said booking an AmaWaterways river cruise through Hill 16 years ago ultimately led her into her current career.
"It was because of a nudge from him that I entered the travel industry shortly thereafter and haven't looked back," she said.
Clare Dudley, Managing Director at Over-based Ponders Travel, said: "James was one of the most endearing people I knew. Always full of life and knowledge. Always happy to share his love of the world's rivers and always happy to tell a tale.
"I will hold on tight to all my wonderful memories and send my thoughts to his family at this very sad time."
Cruise veteran Bernie Carter, who is currently a consultant at Atlas Ocean Voyages, said Hill's legacy would be remembered for far more than his expertise.
"Like a great many of us, I have known James for longer than I can remember; always affable, knowledgeable and happy to share his knowledge and passion with others," Carter said. "Above all, he was our friend. We will miss you James – you really were, are and will always be a true legend."
Michelle Daniels, Viva Cruises' UK and Ireland Country Manager, said: "Such sad news! James was a true gentleman and the oracle of river cruising. He will be very sadly missed. Rest in peace James."
Sarah Weetman, Head of Trade Partnerships at Kuoni, wrote: "Oh no! This is so sad, loved James and the joy he brought to our industry. Thoughts with his family and friends."
"Very sad news. He knew everything there was to know about river cruising and was a great character. He loved winding me up during each Ashes series especially. RIP James," wrote Lockie Kerr, of Inspire My Holiday.
Cruise365 boss Anthony Blackmore said: "So sorry to hear this. A true gentleman. RIP James."
The Hill family have asked for condolences and memories to be sent to jameswalterhill1950@gmail.com.
