Did you know that many river cruise boats carry bicycles on board for guests to use? The bicycles are (or should be) well-maintained and capable of fitting guests of all sizes. Your ship often will have helmets and, of course, a liability form for you to fill out. If you’re squeamish about wearing a helmet that someone else has worn, carry your personal bike helmet. Simply strap it onto the outside of your carry-on luggage so that it doesn’t take up precious space inside your luggage. Or pack a foldable helmet. You’ll need to ask your local bike shop or do a web search for those.