I agree with Andrew L. Those are excellent examples.
Also, students used to American spellings have problems with British spellings - center / centre etc. It seems simple for us, but seems to throw many of them off.
I like where you're going with place names and I agree we don't usually teach them, because we are more concerned with "basic conversation" skills.
But it would make a fun and useful course in itself!
Place names are really odd, and why do the oddest seem to come from the East Midlands?
Take Leicester, for example. Nobody expects it to be spelled like that; why not LESTER? they all complain.
When they read it, they all read LEY CES TER.
Then there is Warwick. Why not Warrick?
And the twin of Belvoir is Beauchamp! What a fancy spelling for the humble pronunciation "Bee Cham! " (I apologise to all the French! Of course, Beauchamp is perfect for their pronunciation (Bo Sham) ... see, I can't even spell that phonetically!)
Let's not forget Beaumont, which brakes the Leicestershire rule and is actually pronounced "Bo MonT!"
If you are organising home stays and tours, then it is fun and important to make your students aware of all this confusion.
However, most of them have a hard enough time knowing when live is pronounced LIV and when it is pronounced LAIV.
There are so many of these simple 4 letter words (read/read; lead/lead/ etc.) which in my opinion are probably the hardest words to read, but not necessarily to spell.
Also TEFL teacher!