The Solar Impulse 2 airplane, flown by test pilot Markus Scherdel, flies off the coast of Oahu during a test flight from Kalaealoa Airfield in Kapolei, Hawaii, March 3, 2016. The solar-powered plane is ready to continue its revolutionary voyage around the world. After the craft was grounded in Hawaii last July due to overheated batteries, it was repaired and upgraded, and a recent initial test flight proved successful. (Photo by Eugene Tanner/Reuters)

Musher Justin Savidis' dogs wait in the truck before the restart of the Iditarod Trail Sled Dog Race in Willow, Alaska March 6, 2016. Mushers and dog sled teams from around the world embark on the first leg of Alaska's grueling Iditarod Trail Sled Dog Race, starting a nearly 1,000-mile (1,609 km) journey through the state's unforgiving wilderness. (Photo by Nathaniel Wilder/Reuters)

“DC3 Wreck”. A capture of a US military DC3 plane wreck at the southern black beach in Iceland. Photo location: Iceland. (Photo and caption by Naian Feng/National Geographic Photo Contest)

The Queen Mary 2 is saluted by the HMB Endeavour, the replica of Captain James Cook's ship, on March 4, 2012 off the coast of Victoria, Australia. (Photo by James Morgan/Carnival Australia via Getty Images)

Tourists take a “selfie” as demonstrators burn a trash container during a May Day rally in Barcelona, Spain, on May 1, 2014. Tens of thousands of workers marked May Day in European cities with a mix of anger and gloom over austerity measures imposed by leaders trying to contain the eurozone's intractable debt crisis. (Photo by Manu Fernandez/Associated Press)

“Theyyam”. Preparation for the Theyyam performance in the surroundings of Kasaragod city. Theyyam is a popular ritual dance form of North Kerala, particularly in Kannur and Kasargod districts. The Theyyam represents a mythological, divine or heroic character. Make up of Theyyams is done by specialist. There are different types of face painting for which primarily and secondary colours are used. Therefore it is essential that the makeup man should have perfect knowledge of primary and secondary colour combinations. Sometimes, it takes several hours to paint each face. Photo location: Kasaragod, India. (Photo and caption by Rafal Ziejewski/National Geographic Photo Contest)

While communism, collectivism, worms, dry rot and casual looting failed to destroy the majestic wooden churches of Russia, it may be ordinary neglect that finally does them in. Dwindled now to several hundred remaining examples, these glories of vernacular architecture lie scattered amid the vastness of the world’s largest country. Just over a decade ago, Richard Davies, a British architectural photographer, struck out on a mission to record the fragile and poetic structures. Austerely beautiful and haunting, “Wooden Churches: Traveling in the Russian North” (White Sea Publishing; $132) is the result. Covering thousands of miles, Mr. Davies described how he and the writer Matilda Moreton tracked down the survivors from among the thousands of onion-domed structures built after Prince Vladimir converted to Christianity in 988.

How sure are you of your geographical knowledge? Buzzfeed recently put Americans’ geographical knowledge to the test with a survey in which participants had to write in countries’ names on a blank European political map. Unfortunately, they didn’t fare too well, but some of their responses are hilarious (or hilariously mis-informed). But don’t be so quick to judge Americans – when Buzzfeed posted a similar survey testing Brits’ knowledge of the 50 United States, they also came up short. On the one hand, knowing a country’s states is different from knowing independent countries, but on the other, some U.S. states are larger than some European nations, and some U.S. states have larger economies than some European nations.