There are 26 in total....
Okay, this is a tough one, even just for the sheer volume of countries in Europe which contain the letter 'R'.
To clarify, we mean all of Europe, not just the EU countries and before it causes any confusion, that includes the individual countries of the United Kingdom.
There are 47 official countries in all of Europe and we are asking you to name over half of them in 10 minutes or less. It's a big ask, but we're confident most of you will get there, or very close.
You can play the quiz below, or if it's not displaying properly, just click on the link here.