Nearly 70 years have passed since the last shot was fired marking the end of World War II. But to look at headlines that emerged out of Germany this week, it may comes as a surprise that there are still bombs left behind from the conflict still waiting to go off.

Earlier this week, a 550-pound American-made bomb dating back to World War II was intentionally detonated in a controlled burst after its discovery by construction workers in the city of Oranienburg.

ANALYSIS: 200 Tons of Silver Found on WWII Ship

Although it was a managed explosion, officials still evacuated some 2,500 residents surrounding the blast area. The explosion shattered windows near the site and set roofs ablaze. But thanks to careful planning, the bomb didn’t claim any lives.

But that’s not all. On Thursday, a second bomb that was discovered was also detonated in the same city near the train station. It, too, had to be detonated, because moving the explosive was simply too risky.

Though it’s uncommon for two WWII-era bombs to be found and detonated in the same city within 24 hours of one another, it should come as no surprise that these explosives are lurking beneath what are now quiet urban or suburban areas. During WWII, when the whole nation was turned into a battlefield, some 22,000 bombs were drilled by the Allies on Oranienburg alone, according to NBC News.

DNEWS VIDEO: Divers Plumb Depths for U-Boats

BIG PIC: WWII Fighter Plane Recovered

Since 1990, when officials first began searching in Germany for unexploded ordinances, more than 130 such weapons have been uncovered. After the war, Germany recovered, but did so unevenly.

West Germany enjoyed the support of the Allies from the United States and Western Europe. The country developed into a commercial and industrial force. East Germany lagged behind, however, until the two states were reunited following the fall of the Berlin Wall. Then, East Germany underwent massive redevelopment efforts to catch up to the West, all funded by German taxpayers. These development efforts can lead to the discovery of unwanted historic artifacts.

In some cases, bombs can be moved. In other instances, they have to be detonated because the ordinances are simply too deteriorated and fragile to risk moving them. In the case of the 550-pound bomb, the device was equipped with a chemical trigger instead of a mechanical one, making simple defusal much more risky.

As Rose Eveleth writes on, the 550-pound bomb isn’t even the largest recent discovery. Last year, German officials discovered a 1.8-ton explosive dropped by the British Royal Air Force during World War II near Koblenz. In that case, however, bomb removal experts defused the device simply by wrenching off the fuse.

Although these latest cases have made headlines, unexploded ordinances are discovered all the time, as the Atlantic’s Alexander Abad-Santos notes. In fact, some 5,500 bombs discovered in Germany are defused every year, an average of 15 per day. During World War II, the Allies dropped some 2 million tons (or 4 billion pounds) of explosives, with experts estimating that anywhere between 5 and 15 percent did not detonate.

BLOG: World War II Shipwrecks Pose Oil Spill Threat

Germany isn’t the only European country dealing with unwanted reminders of a war that took place generations ago. In fact, officials at Amsterdam’s Schipol airport, one of the biggest transportation hubs in Europe, had to close down part of the facility following the discovery of a WWII-era explosive.

And in Poland, a 1.5-ton bomb brought Warsaw to a standstill, according to a Reuters report. Unlike the other explosives, this bomb was of Nazi origin, rather than dropped by the Allies.

Thankfully, given how much practice bomb defusal teams have had with removing unexploded ordinances dating back to WWII, no injuries or deaths have been reported of late, and property damage has been kept to a minimum.

Photo credit: Corbis Images