As usual with any city the problem is finding somewhere to park/camp that is close to public transport. In the case of Ottawa the best we could find was Ottawa Municipal Campground, 411 Corkstown Road, Nepean, Telephone (613) 828-6632. (N45.32960 W75.86696). You will probably need to book, by phone.
On the first day we walked from the campground to the Eagleson Park and Ride (we were told it was less than 2km). It isn't! it is 4.3km! On the second day we drove. The parking is free, the excellent bus service (number 96) costs $Can 3.30. Get off at Mackenzie King.
Ottawa, like Quebec City, but unlike Montreal, has a friendly compact feel. The two highlights for us were the Museum of Civilization...
...and the National Gallery.
The war museum was also highly recommended, but it was too hot.