Linz's massive main square, the Hauptplatz, is the lively city center, lined with pastel-colored buildings and cafés. In the middle of the square is the white marble Trinity Column, erected in 1723.

The Stockholm Wood City, spearheaded by developer Atrium Ljungberg, is being erected in Sickla, a former industrial area ...

Founded in 6000 BCE, Plovdiv, Bulgaria, is considered Europe's oldest continuously inhabited city. Known as the city of the seven hills, Plovdiv has 200 archeological sites and ancient ruins ...

However, its modern soul also shines through at every corner. Sofia is now a major tech and start-up hub in Southeast Europe, drawing international attention and talent.

As I zipped to the top of Varso Tower in a glass-enclosed elevator, I marveled at the city's evolving landscape. At 1,020 feet, the neomodern structure is the tallest building in the EU.