River cruising is the new go-to holiday for those who want to take a break and still stay in shape, says Lee Beaumann.

“This is your last chance to go back,” guide Evelyn warns as we reach the point of no return in our hike up Holy Mountain in Heidelberg. I’m puffing and panting along with the rest of my group but w…

“This is your last chance to go back,” guide Evelyn warns as we reach the point of no return in our hike up Holy Mountain in Heidelberg. I’m puffing and panting along with the rest of my group but we river cruisers are made of stern stuff. We’ve made it this far, up a path so steep that even goats would struggle, and no one is about to give up.

If that doesn’t sound like the usual kind of river cruise excursion, know this: Life on the rivers is changing as the new generation of 50 and 60-somethings seek to mix learning about the origins of baroque and Europe’s religious wars with staying as active on holiday as they are at home.

Cue a new selection of hiking, cycling, kayaking and jogging excursions, a range of activity-themed itineraries from Avalon Waterways and even a new name in river cruising that’s dedicated to revving trips ashore up a gear or two.

Called U by Uniworld, it was created with millennials aged 21 to 45 in mind but has been opened up to all as so many baby boomers wanted to have a go at the paragliding, rock-climbing and white-water trips on offer.

The easy options

Hiking and cycling are the most popular activities in the river cruise lines’ portfolios because they are generally not too strenuous, you don’t need a particular skill to join in (it goes without saying that cyclists do need to know how to ride a bike though) and you see things other than superb cathedrals and splendid architecture.

My hike up Holy Mountain, offered on AmaWaterways’ Rhine cruises, took us to what looked like an ancient Greek theatre but was actually a former Nazi rally ground built by forced labour in the 1930s. At a little over five miles up and down, walking on forest trails rather than tarmac, it is one of the company’s most testing hikes, but there other less strenuous ones for those who like to keep active.

They include hikes to the fortress above Durnstein on the Danube where Richard the Lionheart was imprisoned in 1192 (it’s not a long walk but a steep slope that gets the calves screaming) and to the ruins of the castle he built in Les Andelys on the Seine in the days when England owned parts of France.

Most river cruise lines have bikes on their vessels that passengers can borrow to explore alone or join a guided tour. AmaWaterways has bike tours along the Rhine from Mannheim and around the city of Cologne. From Passau, Germany, a near 14-mile bike ride goes along the Danube to Erlau.

Other river cruise lines in on the active act include Emerald Waterways, which has a 13-mile guided bike ride along the Moselle from Bernkastel to Traben Trarbach on its eight-day Classic Rhine cruises between Amsterdam and Mainz. It also has hikes to the former Ottoman rock fortress of Belogradchik on cruises along the Lower Danube.

You can get in the mood for a mature red on a hike through vineyards in Tain L’Hermitage on the Rhône with Uniworld River Cruises – thoughtfully the company has factored a wine-tasting into the walk. APT offers hikes to Gellert Hill in Budapest on its Danube cruises and guided bike rides around Bordeaux and Lyon on its French river sailings.