The advent of easily accessible satellite imagery in the form of Google Maps and Google Earth has most likely raised the blood pressure of some security experts over the years.

According to The Google Earth Blog, which is not affiliated with Google, when Google obtains imagery from commercial entities or government agencies, those sites sometimes come pre-blurred.

However, laws have changed, new imagery sources have become available, and Google has quietly lifted the veil on many of these secretive sites.

Here are the government buildings, military installations, and industrial centers that can now be viewed on Google Earth, as well as three places that remain hidden from prying eyes.

The U.S. president's digs
House Continues Work On Capitol Hill
(Photo : Anna Moneymaker/Getty Images)

The address 1600 Pennsylvania Avenue in Washington, D.C. was whited out when Google Maps and Google Earth first debuted, as per LiveScience.

It was a brief attempt at national security; comments on a 2005 post on the website Google Sightseeing indicate that the blurring was removed by early 2006.

Whether the lines are blurred or not, the White House is surrounded by multiple layers of security.

According to ABC News, this includes bulletproof glass windows, alarms and infrared sensors along fencelines, armed security teams on the grounds, and sniper teams on the White House roof.

People still attempt to scale the White House fence on a regular basis. They're usually caught quickly, but there have been some major lapses.

In March 2017, a man from California jumped a fence and spent 17 minutes on the grounds with a backpack containing pepper spray, which was a notable failure.

One Observatory Circle

While the White House was quickly visible after Google Maps and Earth were released, the Vice President's residence remained hidden for the duration of Dick Cheney's presidency.

According to a Gawker post from the time, one Observatory Circle in Washington, D.C., was blurred out on Google Earth until January 18, 2009. The slate-roofed 1893 structure and its surrounding grounds can still be seen without pixilation.

The Vice President's residence, like the White House, has extensive on-site security.

Former Vice President Joe Biden allegedly revealed some of those security secrets in 2009, when he told dinner guests about a bunker beneath the house, according to Fox News.

His staff later released a statement claiming that the VP was referring to a secure upstairs workspace rather than a classified bunker location.

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The U.S. Capitol Building

When Google Earth first launched in 2001, another US government site that was pixelated was the US Capitol.

Things worsened before they improved. According to a 2007 Washington Post article, Google first launched its views of D.C. with the U.S. Satellite imagery from the Geological Survey that censored the Capitol and the White House.

The company chose to use imagery that did not block these sites in June 2007, but it was much older (and blurrier).

For a time, Washington, D.C. was a perplexing jumble of crisp USGS aerial photography and blurry, out-of-date commercial satellite imagery. Everything is now in order.

HAARP site

The High-Frequency Active Auroral Research Program is known more for what it does not do than for what it does, as per Travel Triangle.

 HAARP is an Alaska-based program that studies the ionosphere, the upper layer of the atmosphere, in order to improve radio communications.

According to conspiracy theorists, it controls the weather, chemtrails, and people's minds.

Several blog posts and news articles claim that HAARP's facility in Gakona, Alaska, was once blurred on Google Earth.

A look at the program's history page reveals no deliberate censorship of the facility, though there are significant flaws in the satellite data that cover the site only partially until 2013.

Volkel Air Base, the Netherlands

Former Dutch Prime Minister Ruud Lubbers claims that the base bunkers house 22 US nuclear bombs, each with a yield four times greater than the bombs used in Hiroshima and Nagasaki. And you thought Google's abstract artwork was pretty cool.

The censorship of the Volkel Air Base in the Netherlands was not by chance. The air base, which houses a US nuclear weapons repository, was once a patchwork of green and white pixels.

The presence of the nukes became widely known in 2010, when Wikileaks published a diplomatic cable mentioning their existence.

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