The statement was pretty clear, right? Most European countries are less than 500km wide is almost certainly true, no matter how you define width. There are only

The statement was pretty clear, right? Most European countries are less than 500km wide is almost certainly true, no matter how you define width. There are only 8 EU countries that are larger than 500km^2. And that includes the vast spaces of Scandinavia where no one lives. Driving from Warsaw to Lisbon, 6 countries, and crossing 4 of the largest, is 3.300km.