His 6,500-mile round trip, thought to be a new world record, took him across the English Channel, through tense waterways in Serbia and along the tempestuous Danube.
He travelled in a "working pair": two canal barges tied side-by-side, one with a motor and the other for cargo, the traditional way of transporting goods by canal.
After a calm Channel crossing last autumn, he cruised through France, Germany, Austria, Hungary and entered Serbia. "Serbia is a country still technically at war so there were lots of soldiers investigating us and waving their Kalashnikovs around," he said. "A number of times I thought the trip was over."
Disaster almost struck in February on the Danube when storms and choppy waters sank one of his boats in 50ft of water: local divers helped him raise the vessel.
His return leg from the Black Sea port of Constanta was helped by two Romanian vessels which towed him back north against the swift current of the Danube to slower waters near Frankfurt.
A spokeswoman for the Guinness Book of Records said yesterday there was no existing record for a narrowboat trip and the publishers would be happy to examine Mr Sanders' log.
Mr Sanders, a 37-year-old Mancunian, has three times travelled around the world (twice by bicycle and once by motorbike), cycled around Asia, down the length of the Andes, to the source of the White Nile and twice around Britain.
No sooner had he touched land on Tuesday than his sights were set on his next adventure. He set off yesterday for a "victory lap" through the canal network of Britain which will bring him to Chester later this month before he begins writing a book on his odyssey.
"I don't do these trips for charity. I spend months getting sponsorship to fund each one and I do them for fun," he said.
"I might have people chasing me with guns now and then and I might get nasty diseases but people who lead normal lives are just as scared as I am when I'm on an expedition.
"Only they're scared about their mortgages or job security, so I think I'm the lucky one."