This is a historic bridge that was the first constructed over the Missouri River. It was designed to carry vehicle traffic on the upper deck and rail traffic on the lower level. To accommodate the ferry and boat traffic on the river, there's a vertical lift structure as well. Currently, both levels of the bridge are for pedestrian traffic. The lower level has a marking when you cross the state line for South Dakota and Nebraska, but the upper level does not. There are splendid views of the Missouri National Recreational River, although for some reason there was a lot of dog waste on the bridge (gross!). There were a lot of locks present on the bridge, I guess as a thing that couples do. It's a fun activity to do if you're in the area. I would budget about half an hour to walk across the bridge and back, more if you want to spend more time looking at the river. read more