Just a quick orientation note on the rather confusing system of interrupted mountain / gravel bike / trail running system more or less along the Mississippi river north and south of I 494. More to come later. For this orientation I’m using River coordinates — so imagine river actually runs N/S and, going N, the left side is always the West bank, right side always East bank. Part of the confusion surrounding these trails is some people use compass north/south and some use river coordinates.
Fort Snelling State Park doesn’t easily connect to the trail system, there’s a large gap on the west bank due to airport and military zone that’s unlikely to close, to connect you need to climb the bluff and take the I-494 walkway trail to get to the East bank.
From Upper Fort Snelling (or lower park if climb) you can take Mendota bridge to trail that runs along East bank from Sibley House south to 494 (confusingly called the Fort Snelling State Park River Bottoms trail, but it’s easiest to get to from Fort Snelling proper, not the lower State Park or to cross the river to Sibley House area.)
A mile or so south of Fort Snelling State Park (you can’t get there thanks to restricted military/security zone), on the West Bank, south of 494, there’s a state park visitor center. From that you can do a loop along west bank that crosses at 77 to east bank and returns on 494 — this includes par of the east bank trail. (There used to be an unofficial way to get from near this visitor center to the next trail south on west bank, but I don’t know if that works now.)
From Old Cedar Ave (9500 Old Cedar Ave South, 55425) you can connect up with 2 trails on the west bank, one runs north, the other south. This is often called the Bloomington Ferry Road Access Point or “west end” (it’s on west bank) entry point, and this is the trail MORC describes as “Minnesota River bottoms” (though it’s really just one segment).