So if anyone's wondering whether a tricycle could be the solution to their $Problem (whatever the problem is), come and visit me sometime during the next couple of weeks. We can take the trikes down to the park by the river where there are tarmaced paths, gravel paths and grass, plus flat bits and mildly hilly bits, and you can see if it works for you. My current trike is adjustable to a range of heights, although anyone much under 5'0" or over 5'9" will have trouble. (One of the reasons I'm getting a new one is to deal with the fact that, even pulled as far forward as they can possibly go, the handlebars are a bit too far away to be comfortable for prolonged use.) If you feel brave enough to deal with traffic, we have a range of roads from extremely quiet (less than 1 car per minute) to extremely busy (Kingston one-way system).