This mountain city in Bulgaria is known as the Machu Picchu of Europe but is less crowded and easier to get to, while still full of ancient mysteries.

A study shows that only about 30% of those displaced by conflicts return home, even 10 years after the conflict ends.

Australian authorities disagree over the response the country should take to the runaway success of the Chinese AI app ...

New research has found that data centres can reduce their energy usage by up to 30% simply by altering around 30 lines of ...