For the people loving cycling (or walking) along a river, the Thames path (https://www.nationaltrail.co.uk/en_GB/trails/thames-path/) is definitely worth it. We cycled no more than a London section of the path, kind of 3 days down the river from about Richmond and Brentford to the Angel Inn at Bermondsey Wall East and back upstream to where we started.
“Following the greatest river in England past water meadows, unspoiled rural villages and all through the heart of the big city” as the website indicates. Even though the path is mentioned to be walking oriented, it was easy cycling. We never had the feeling to be wrong cycling this path. If needed/wanted there are plenty of alternatives and countless wonderful places to stop and visit or stay.
The pictures are not in the chronological order and mixed cycling down and upstream. A ride like this doesn't need any preparation apart of keeping an eye on the weather forecast…
We look forward cycling the entire path one day.