San Jacinto River near Conroe, TX this afternoon at about 2:30 pm.
crossed the Detroit River last weekend. Though I went under it rather than going about it the hard way.
The last one I crossed that goes by the name of river was the Great Works River while driving on Friday. Where I crossed it, it’s all of 20 feet wide, at most. Four times today on my walk I crossed an unnamed stream that’s probably twice as wide.
The river that separates childhood from old age, many times a day.
I’m originally from upriver and used to cross the “Skookl” regularly.
These days I cross the Thames pretty much every day, assuming that passing under it counts as “crossing”.
I crossed the River Avon on my way to work this morning, deep in Shakespeare’s country.
From the bridge you get a view of our town’s medieval castle which has been guarding this stretch of the river for at least 1000 years.
My nearby fellow expats and I frequently need to travel to Nakhon Sawan, our nearest big city. We all live on the west side of the mighty Chao Phraya River, and Nakhon Sawan is also on the west side. However the best and most direct route is the highway which follows the east shore. Hence we cross the Chao Phraya River four times on each round trip to the big city.
Six times on Saturday, all on foot.
The Patapsco River - underwater - via the Harbor Tunnel - I crossed it yesterday on my way to my mom’s and I’ll cross it today on my way home. I used to cross the Potomac every day on my way to work and the Patuxent when we still had a boat and kept it in Solomons. I love living in the Chesapeake Bay area!
I crossed the Cuyahoga and the Chagrin twice yesterday.
The Piscataquog; walked out to the other side of the bridge and back on my Saturday morning walk. 
Middle Patuxent, most likely. But it’s so little I’m not sure it counts.
Do estuaries count? If so, then I went across the Humber Bridge over the Humber. We were visiting friends in Hull but decided to detour and cross the bridge for the hell of it.
The Shannon on a ferry a little over a month ago.
ETA: Now I think about it, I crossed the Potomac a few days after that, on the way home from Dulles airport. It was a much less memorable journey, however, in a shuttle-bus on the Beltway.
By car, it would have been the K’wanza river about 60km south of here. By air, it would be the Congo river.
I was up there a few weeks ago. You don’t get far up 61 without crossing water. It is so beautiful. Did you know the north shore is some of the oldest rock on earth.
I cross the Mississippi about half the time I leave my house. I see it out my bedroom window.
The mighty Fox River yesterday.
If you take major continental American rivers to be the ones that are named on this map, then the only ones I have not crossed are the Kennebec, James, Red, and Humboldt Rivers. I was going to add the Connecticut but when I was in Vermont once I crossed it on foot just so I can check New Hampshire off on the states I’ve visited.
The Maribyrnong.
ETA: A few hours ago. I live practically next to it, so I cross it fairly often.
On average I cross the Mississippi River 10-20 times a week, most recently last Thursday. ( I took off of work today.)