Get immersed in the heart of the Austrian capital by discovering its most emblematic sites, from museums to cathedrals and opera houses.

That’s far less than in the U.S., which tops the ranking with 120 firearms per 100 residents, but more than Austria’s neighbor Germany, which ranked 23rd with 19 firearms per 100 residents.

Officials in Austria say a school shooting has left at least 10 people dead in the European nation's second-largest city, Graz. The shooter is also dead.

In February, a 23-year-old man stabbed five passersby in southern Austria in what police said was a random attack. CNN’s Rob Picheta, Lauren Kent and Saskya Vandoorne contributed to this report.

Austria, with a population of 9 million, has one of the most heavily armed civilian populations in Europe, with an estimated 30 firearms per 100 people.