Salar de Uyuni in south-west Bolivia was once part of a massive prehistoric lake but today is the world’s largest salt flat. When dry it’s a barren landscape, so featureless that it’s great for perspective tricks – but during the wet season it becomes a spectacular giant mirror.

Salar de Uyuni is estimated to contain as much as 10 billion tonnes of salt, and about 25,000 tonnes is collected here each year, using the traditional method of sweeping the salt up into neat piles to dry before being carted away.

However, salt is not Salar de Uyuni’s only valuable mineral: it also contains an estimated 5.4 million tonnes of Lithium, which is estimated to be between 50% and 70% of the world’s entire lithium supply! As a vital part of many electric batteries demand for lithium is on the increase, but Bolivia has been reluctant to let foreign mining companies onto the flat, instead opting to build their own modest plant which should be operational by 2012.

In the meantime, Salar de Uyuni still helps the economy through tourism. Hotel de Sal Playa Bianca, or “The White Beach Hotel” was built right in the middle of the salt flat and constructed from the very same salt. Unfortunately, due to the difficulties in sanitation, it was closed down in 2002.

Thankfully tourists can still experience living in a house of salt at either Hotel Luna Salada or the newer Palacio del Sal, both of which are built just on the edge of the salt flat. In an effort to protect their building from degradation, the Palacio del Sal enforces a strict “no licking the walls” policy.

Tourists to the area may also take a visit to Incahuasi island, also known as Island of the Fish. Located within the salt flat it is technically not an island, and is home to no fish. If that doesn’t tempt you, you could always visit the nearby town of Uyuni, which has a massive train boneyard.

Where the North Sea meets the Baltic Sea¹, there’s Grenen²; a spectacularly unspectacular sandbank at the northern end of Jutland, the continental part of Denmark.

The form and position of the sandbank’s tip can vary considerably over short periods of time, when waves³ and currents remove or deposit sand.

On the long term however, Grenen is growing by almost a kilometre (roughly half a mile) per century, slowly extending towards the north east. A closer look at the aerial picture shows distinct stripes in the landscape: successive layers of silt and sand that have accumulated over time.

Of great importance is the 46m (150ft) high lighthouse close to the tip.

Despite the increasing use of advanced navigational systems, the lighthouse is still crucial to the safe passage of more than 100,000 ships that pass Grenen every year.

Due to its prominent position in between seas, the location has also been of great military interest for many years. What remains today are several very sturdy concrete fortifications and artillery positions built by the Germans during World War II.

These structures are part of the huge Atlantic Wall project, a chain of coastal defences built by the German Third Reich that runs from southern France to the northern end of Norway. The Wall was never completely finished, and save its French parts never saw much use.

A little further to the south lies the “Tilsandede Kirke“, or “silted up church“. Built around the 12th century, it was the region’s most important church.

However, beginning in the 16th century, it had to regularly be dug out of the sand that amassed around it, and was finally given up in 1795. Its main building was torn down to reuse the building materials, while the church’s tower remains as a historical site.

Grenen today is a popular leisure destination⁴ and a nature reserve, protecting the region’s distinct vegetation including several kinds of orchids. It is also a popular site for bird spotters looking for passing eagles, ospreys, cranes, storks and ernes, amongst many others.

New writer: Noel Ballantyne Noel is from Sligo, NW Ireland. He is a very active member of the GE BBS forums, and loves to travel, especially to concerts when band’s tours do not visit Ireland.

A common topic of conversation for most kids in school goes along the following path: “What is the tallest/smallest/fastest/slowest/most expensive?” etc. I think you know what I’m on about.

“What is the biggest waterfall in the world?” I was asked recently. After much discussion about widest, tallest, flow of water etc., we settled on the tallest.

The tallest waterfalls are the Angel falls with a height of 979 m (3,212 ft) and a clear drop of 807 m (2,647 ft), which are located in the Canaima National Park¹ in the Gran Sabana region of Bolivar State, Venezuela. Unfortunately the resolution in Google Earth is poor to say the least.

However at Ciudad Bolívar airport in Venezuela we can see Jimmie Angel’s plane. Jimmie Angel is the first Westerner accredited with seeing the falls in 1933. In 1937, Jimmie and his 3 passengers set off in his Flamingo monoplane “El Rio Caroni” to land atop of the falls.

Well, it was more a crash land actually, where the wheels became bogged down in marshy ground and flying home was no longer an option. An 11-day hike gave the adventurers worldwide fame and the falls were subsequently named after Mr. Angel.

In 1970 the Venezuelan military disassembled the plane and it was re-assembled in the city of Maracay’s aviation museum. A replica of the plane sits on top of the falls themselves.

Angel got all the fame for discovering the falls, but there are 2 others also in the picture. Sir Walter Raleigh is claimed to have discovered the falls on an expedition to find El Dorado in 1594. In 1910 or 1912 Ernesto Sanchez La Cruz, a Venezuelan explorer, is also said to have discovered the falls – in fact some texts actually credit Jimmie Angel as the rediscoverer. Another first goes to Aleksandrs Laime² from Latvia who was the first to reach the falls on foot.

There’s some stunning photos of the falls on Flickr, and further history on Wikipedia.

New writer: Randy Nickum Randy is a lifelong resident of Cincinnati, Ohio, in the Midwest U.S. He has travelled widely across his country as a consultant and has visited six of seven continents, missing only Australia so far.

An exclave is defined as “a territory whose geographical boundaries lie entirely within the boundaries of another territory.” Practically speaking, it is a portion of one territory that cannot be reached by land without first passing through another.

There are several examples of exclaves in the United States. One of the best known (and previously documented on GSS) is Point Roberts, Washington, an area of the state that can only be reached by first travelling through British Columbia, Canada.

The exclave of Point Roberts was created by the 1846 Oregon Treaty, which set the boundary between the United States and British North America at the 49th parallel north — with one exception. Due to various mapping mistakes and confusion over the location of the headwaters of the Mississippi River, the U.S.-Canada border juts northward to include a chunk of land lying north of the 49th parallel. This area, now part of the state of Minnesota, is known as the Northwest Angle.

The Angle (as it’s known by locals) can only be reached via a single gravel road through Manitoba, and visitors clear Customs in both directions via videophone in a small unmanned hut. The total population of the remote, 300 square km (116 square mile) township is 152, and it boasts the only remaining one-room school house in the state.

Just below the 49th parallel, and also cut off from the mainland of the U.S., is Elm Point, Minnesota. Elm Point is remote, uninhabited and roadless, yet satellite imagery appears to show a line cut through the forest at the U.S.-Canada border, presumably for clear sight lines along the border. Who would see any illegal activity along those sight lines is an unanswered question.

Alburgh, Vermont is a pene-exclave of the United States. Now before our dear readers crash the GSS servers thinking a pene-exclave is some sort of French rudeness, a bit of definition: a pene-exclave is an exclave for practical purposes, without meeting the strict definition of an exclave. In the case of Alburgh, the town lies on a peninsula connected to Canada (like Point Roberts and the Northwest Angle) but is linked to the rest of Vermont and neighbouring New York via bridges. These bridges serve as the only road route across Lake Champlain.

Among state borders within the U.S., many exclaves have been created over time by the meandering of flooded rivers. In these cases, legal boundaries remain in force, even though river courses render some areas cut off from the rest of their respective states. Among the most prominent examples are the Kentucky Bend and Carter Lake, Iowa.

The Kentucky Bend is an area of Kentucky that is completely surrounded by the states of Missouri and Tennessee. The Mississippi River passes over a geological fault in this area, and The Bend was formed by a shift in the course of the Mississippi River after an earthquake in 1812. A later surveying mistake (again with surveying mistakes?) while setting the Kentucky-Tennessee border created the division. The 44 square km (17 square mile) area is home to just 17 people. No bridges connect The Bend with the rest of Kentucky, and if you wish to send mail to someone in The Bend, his official postal address is (confusingly) in Tiptonville, Tennessee.

Finally, Carter Lake, Iowa is the only city in Iowa that lies west of the Missouri River. It is completely surrounded by Omaha, Nebraska, and was formed by a flood that straightened the course of the river in 1877. After a set of legal disputes Carter Lake was determined to be part of Iowa, and later became a recreational hot spot, offering casino gambling even though the rest of surrounding Nebraska outlaws it. The town’s utility services come from Nebraska, while children attend school across the Missouri River in Iowa. Travellers in Omaha driving to the city’s airport pass through Carter Lake¹, where signs reading “Welcome to Iowa” confuse many panicked out-of-state visitors.

You can read more about the Northwest Angle, Elm Point, Alburgh, the Kentucky Bend, and Carter Lake (along with a huge worldwide list of exclaves and enclaves) at Wikipedia.

For centuries, the source of the mighty River Nile was shrouded in mystery in the dark heart of Africa. In Roman times, the phrase caput Nili quærere, “to search for the head of the Nile”, was used as a metaphor for any foolish or impossible endeavour, and many explorers tried and failed to reach the fabled “Mountains of the Moon” from which the river emerged. Nowadays, thanks to Google, we can explore the whole river from our desktop, without even having to get dressed.

The Nile, of course, is not a single river. It is formed from two main tributaries, the White and Blue Niles, which join at Khartoum, in Sudan¹

Although the Blue Nile is the shorter tributary, it contributes the majority of the water. Its source is in the highlands of Ethiopia, supposedly at a sacred spring near the town of Gish Abay. This site has been known to Europeans since a Spanish missionary, Pedro Páez, visited in 1618. The aerial imagery suggests, however, that the stream actually begins some way beyond the town.

The White Nile is the longer branch, and so the source of this river is the true beginning of the Nile. In 1858, the explorer John Hanning Speke became the first European to see Lake Victoria, which he claimed to be the fabled source. Four years later he journeyed to Ripon Falls (now submerged by a dam), where the White Nile exits the lake.

Although Lake Victoria is still often considered to be the source, the Nile can actually be traced back further, to the headwaters of the longest river flowing into the lake. It turns out that this is the Kagera River, and its remotest source was traced to the hills of Burundi by a German, Burckhard Waldecker, in 1934. His discovery is commemorated by a pyramid erected on the summit of Mount Kikizi, just above the true source… which, judging by this photograph, appears to be a small plastic pipe used by the locals for doing the washing up!

So does that settle the age-old question? Not quite. In 2006, a team of explorers from New Zealand and Britain travelled to what they claim is the most distant source, in the Nyungwe Forest in Rwanda. Unfortunately the imagery here is low-res, but you can see a photo of this source via this site (the expedition’s official website appears to be dead).

Who’s right? Without high-resolution imagery, it’s hard to say. What is certain, though, is that the Burundian source is much further south than the one in Rwanda, so – in a straight line, at least – it’s further from the mouth of the river. In theory, it ought to be possible to use Google Maps’ Distance Measurement tool to measure the total length along each little stream extremely accurately. Any readers have a lot of time on their hands?