Someone asked me yesterday if I wanted to watch the Tour de France in person. The answer is yes, but! Because June and July are hot weather months. And yes, because the trip could be sandwiched with the French Open (tennis) at the start, and Wimbledon at the end.
The biggest challenge, other than joining a guided tour, is getting from one venue to the next, since they are not contiguous. Watching on TV over the years, one solution to the rather sprawling location of the routes is renting a motorhome. But as a foreigner, I cannot see driving through the French countryside in a cumbersome vehicle, trying to find a place to park, and a place to view the race. As exciting it is on TV, I think it would be better in person.
Why are the logistics so difficult? Take a look at the routes.
First, the length of the race, from June 26 to July 18 is three weeks (actually 23 days long with two rest days). This year, the race has ten new sites and stage cities. So, there are twenty-one stages, including two time trials.

The best parts for me would be in the south, toward Bordeaux, and the beautiful town of St. Emilion. Though the race always ends on the Champs Elysees, I think I would avoid Paris. My ideal race stages would be, in this order: Champagne, Loire, and Bordeaux.
The race is 3414 kilometers, or 2121 miles long. Of the 21 stages, 8 are flat, 5 are hilly, 6 are mountain stages, and two are time trials. There are 23 teams with 8 rides each, for a total of 184 riders. And of course, not all riders who start will finish, due to accidents or medical reasons.
An American has not won the race since 1990, Greg LeMond. The wins by Lance Armstrong were removed, since they proved he was cheating.
But despite all of the doubts, it would be fun to attend at least once. But visit the French Open and return to Wimbledon!