This one is for photos from the Czech Republic only but @czechglobalhosts runs another daily contest that anyone can join. It is the 7 Continents Photo Challenge with the following schedule:

• Sunday: Asia
• Monday: Australia and New Zealand
• Tuseday: Antarctica + the world’s oceans
• Wednesday: Africa
• Thursday: Europe
• Friday: North America
• Saturday: South America

See his blog for more info ;)