ツアー、旅、旅行、行楽、遠足、見物、観光

I am very lost with the definition of these words and don't know when I should use each of them. I tried to group them using a dictionary but I am not so sure if I did it right. Ideally I wish I can use them interchangeably depend on what I can think of when talking. But yet afraid that it might give inaccurate meaning. Please advice.

見物、観光 => to me, the later one sounds broader?
遠足、行楽 => the later one is broader sense of outing? the first is just excursion?
旅行 => traveling in general (most commonly used?)
旅 => going somewhere in a less concrete sense?
ツアー => if I'm not mistaken, I found it when reading some blog but has forgot the context already. Does any one have seen this? and in what context?

A Japanese friend of mine told me, if I recall well, that 遠足 is used *only* for school trip. E.g., elementary school trip.

I think ツアー means 'visit somewhere with someone who leads or explains stuff '. E.g., 博物館、工場、バスツアー The last definition is IMHO as I can't look for it properly atm.

観光 and 見物 are pretty interchangeable, but 観光 has more of the general meaning of seeing the sights around an area (perhaps even with a tour guide), whereas 見物 tends to emphasize looking at a specific object or site.

旅 and 旅行 are used without much discrimination between the two. Again, there is a bit of a nuanced difference - 旅 carries the idea of a slow, extended, leisurely trip, whereas 旅行 infers travel for fun and excitement. So I may call a meandering trip across Japan by rail, with frequent, relaxed stops, 旅. But I might refer to an excursion to Taiwan over Golden Week as 旅行.

Again, though, most people don't seem to consider this nuanced difference when using these words.

Shakunatz is right about 遠足; it refers specifically to school field trips.

行楽 is a general family/friends excursion to the countryside for a picnic or some such. I think most people in this instance, however, would just say something like 「（どっか）に遊びに行った」rather than 「行楽に出かけた」.

ツアー is borrowed from English, and is used to refer to an organized, led tour.

Thank you very much. Those really are little areas that I didn't know. Now I my task is to remember them so I can use them appropriately. Thanks!