We're planning a road trip from Virginia up to Ottawa, with a detour to Burlington VT on the way up and a stop in Syracuse NY on the way home to visit family. If we go in October, it'll be early October; if in September it could be any time in the month, depending on work. I know October will be somewhat cooler. Are there other factors that should be considered when deciding which month?

The colours of the leaves are usually at their height in the Ottawa area in the last week of September and first week of October if that's a factor which will help you decide.

Laverendrye's point is a good one (although leaf colour timing and intensity can be variable year to year depending on the summer and early fall weather). The only other thing I can think of right now is that Canadian Thanksgiving long weekend is October 8/9/10 fyi. (The Monday is the holiday, so many things will be closed that day although some of the Tourist Attractions will still open).

Thanks for the info. It looks like work has dictated that we go with October. We'll probably be arriving in Ottawa on Monday 10/10. Are any restaurants in the downtown area likely to be open? (Dh would be ecstatic at the thought of getting Thanksgiving dinner twice!)

I haven't been in Ottawa on the Thanksgiving Holiday, but elsewhere in Canada the trend is for more restaurants to be closed than open on Statutory Holidays, with some exceptions. We were in Ottawa on New Years Day, another Holiday, and many restaurants were closed through the day although some opened in the evening. Tourist areas, such as the Byward Market district of Ottawa, may have more tendency to stay open and it's quite probable that some restaurants that do open that evening would be offering a Thanksgiving Meal option.