I was wondering, has anyone ever seen a highway with 5 or more exits within the same mile or sequence? The most I have seen is 4, where each exit is given the suffixes A, B, C, and D. If there were 5 exits, would the fifth exit be given the suffix "E"? Some states use "E" for exits indicating the eastbound exit, with "W" indicating the westbound exit.
I-75 Cincinnati has exits 1B - 1G
I-90/94 Chicago has exits 51A - 51I
I-70 Kansas City MO has 2A - 2M (1 is skipped for some reason though some of those exits would better fit there.)
I-794 Milwaukee has 1A-1H
I think New York state uses the E/W or N/S instead of A/B for such exits you describe.
On I-395 south, right as you cross the Potomac River, you've got seven exits in 0.7 miles (per my Google Maps mensuration):
Exit 10C - Northbound GW Parkway
Exit 10B - Southbound GW Parkway
Exit 10A - Westbound Boundary Channel Drive/Pentagon North parking
Exit 9 - Eastbound on Boundary Channel Drive (signed as Clark Street, which doesn't exist in that part of Arlington)
Exit 8C - Southbound Jeff Davis Highway (left exit)
Exit 8B - Northbound Jeff Davis Highway
Exit 8A - Westbound Washington Boulevard/Pentagon South parking
Does the alphabet loop in Kansas City count? I know there are over 20 exits its entire loop, so I imagine that at least five are within a mile of each other.
The Atlantic City Brigantine Connector has exits A, B, and E-H (no numbers, just letters), though they are not all within one mile.