It's about 2 miles to the core of St Charles where the pubs/ coffee shops are so be the judge as to whether you'd want to walk that far.
yes parking is kinda hard to find. we part behind the Arcadia Theater in some complementary parking and just walked everywhere. it's a nice town.
You will need a car to get around Saint Charles and other towns.
No, but it is a short uber ride!
I think it would be a long walk.
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