Illinois Route 33 runs east-west in southeastern Illinois, connecting the Effingham area to points east. The western end is a little west of Effingham, near Beecher City, and the eastern end dives south along the Wabash River to end just across that river from Vincennes, Indiana.
The western end of Illinois 33 is at Illinois 128 near Beecher City (not to be confused with Beecher, which is in Will County):
Illinois 32 joins from the north to ride Illinois 33 eastward into Effingham...
In Effingham, Illinois 33 meets US Route 40 and joins it eastward, as Illinois 32 comes to its southern ending:
Right in downtown Effingham, as Illinois 33 and US Route 40 are going eastward together, US Route 45 joins from the south...
The triplicate concurrency only lasts a few blocks, however, and US Route 45 soon diverts northerly from Illinois 33 and US Route 40...
Only a few blocks later, Illinois 33 splits from US Route 40, and both routes exit Effingham heading easterly at different latitudes:
After passing through Dieterich and Wheeler, Illinois 33 reaches Newton, where it joins Illinois 130 north:
Only a few miles later, outside of Newton, Illinois 33 splits from Illinois 130 to resume going easterly:
Near Willow Hill, Illinois 33 crosses Illinois 49...
Immediately after serving as the main drag through Robinson, Illinois 33 crosses Illinois 1...
Illinois 33 turns southerly for over fifteen miles, along the Wabash River, to pass under US Route 50 and meet the bridge carrying Indiana 441 over the river out of downtown Vincennes:
The southeastern end of Illinois 33 is strange; having passed under US Route 50 alongside the Wabash River, Illinois 33 reaches the bridge carrying Indiana 441 out of downtown Vincennes into Illinois, and Illinois 33 bends northwest as a sort of access road to US Route 50. Illinois 33's southeastern end is at US Route 50 where this access road meets that route, but drivers from Illinois 33 are ironically facing northwesterly at this point...