Does Mount Everest's Altitude Start from Here?

China is so vast, I want to see it. Let me take you to a place you might have visited or not.

Does Mount Everest's Altitude Start from Here?

On May 27, 2020, eight members of the Mount Everest elevation survey team successfully reached the summit and smoothly carried out all summit measurement tasks. This was China's third survey of Everest's height.

(Photo from internet)

We all know the concept of altitude above sea level – simply put, it's the height of a point on the ground measured from mean sea level. But in practice, taking that measurement is not straightforward. For one, sea level differs from place to place. Even at the same location, the sea surface constantly changes with waves and tides, making accurate measurement impossible.

China uses the mean sea level determined by the Qingdao Tide Gauge Station as its vertical datum. Qingdao was chosen because, first, it lies in the mid-latitudes and can better represent the country's average sea level, making it easier to transfer elevation data elsewhere. Second, the sea area off Qingdao has typical semi-diurnal tides, and Jiaozhou Bay, where the tide station is located, experiences small waves and a stable sea surface, ideal for tidal observations. Third, Qingdao has stable geological structures. Fourth, tide measurements began here as early as 1900, and a formal tide station was established in 1904 – operating almost continuously ever since. With rich scientific records covering astronomy, oceanography, meteorology, and tides, it helps precisely determine the national mean sea level.

This time I visited the "China Level Zero Datum Scenic Area" inside Qingdao's Yinhai World. The level zero point here is the only one of its kind in the country. Note, this is a scenic area – more on that later.

The Level Zero Monument is a bronze sculpture, 6 meters tall. On top, a globe features six small balls, symbolizing six famous altitude origins around the world. Below, it resembles a plumb bob. Beneath the sculpture is an observation well, and at the bottom of the well sits a red agate ball. The tip of the plumb bob points right at the top plane of that ball – this is the "China Level Zero Datum" determined by experts, also called the altitude base point. It's China's zero-meter altitude, the "mother of all elevations in China."

The agate ball with its flat top plane marking "0" meters (white dot).

The platform of the observation well where you stand is at an elevation of 4 meters.

And that's how Mount Everest's height works.

Once you've experienced "altitude starts here," you might think China's elevations are measured from this "level zero point." But that would be wrong.

The true starting point for altitude measurement is the "Level Origin" – and it's unique. The "Level Origin" is the benchmark for transmitting elevation data through the national height control network. China's Level Origin was not built right by the sea. The main reason is that with constant wave movement, the mean sea level measured by the tide gauge cannot be directly observed; the sea surface changes with tidal cycles, and a seaside location is also difficult to protect. So the Level Origin needed to be built near the tide station but on a more stable, reliable piece of land, serving as a permanent reference point. This "Level Origin" was built on the top of Guanxiang Hill in Qingdao.

On Guanxiang Hill stands a mysterious Russian-style stone house, entirely built of Laoshan granite. Into its wall is set a stone tablet carved with the characters "水准原点" (Level Origin). Inside the house, at the bottom of a dry well, lies a fist-sized agate with a hemispherical top. The very top of that hemisphere is the "China Level Origin" determined by the National Bureau of Surveying and Mapping. Tempted to go inside? Think again – it's not open to the public.

Construction of the Level Origin began in 1954 and was completed in 1957, establishing China's first unified height datum, known as the 1956 Yellow Sea Height System, with the origin at an elevation of 72.289 meters. Starting in 1975, the country carried out new measurements. Based on tidal records from the Qingdao Dagang Tide Station from 1952 to 1979, the final calculation set the Level Origin elevation at 72.2604 meters under the "1985 National Height Datum." This is the starting figure for elevations, the reference point for the country's height control. In other words, Mount Everest's height is measured from this "Level Origin," and adding 72.2604 meters gives you its altitude above sea level.

"Level Origin" and "Level Zero" may sound confusing, but the "Level Origin" is the true reference point in the national height network. In 2006, to make better use of this unique resource, the National Bureau of Surveying and Mapping approved the precise transfer of the Level Origin's data to create the "China Level Zero Datum" in Qingdao's Yinhai World. In other words, the "Level Zero" is a sea-level "0" meter point extrapolated backwards from the Level Origin. It's approved by the national surveying authority and is the "one and only." It serves as a tourist attraction of special significance, with educational value – though much of that education is misleading. The vast majority of visitors come, snap a photo, and leave without ever understanding, wrongly believing that elevations start from here.

Let's go back and take a look around the Level Zero Scenic Area. Inside, you'll find displays themed around surveying and mapping culture, maritime culture, and ocean culture. The Qingdao International Yacht Club is also located here.

A 1:1 model of the Jiaolong submersible.

The Italian explorer Christopher Columbus.

The grand eunuch Zheng He, known as the 'Three-Treasure Eunuch'.

A Spek anchor (typically used as a main anchor for large and medium-sized ships).

A capstan (also called a mooring winch, mainly used for hauling-in ropes).

Goddess of the Sea, Mazu – the Heavenly Empress.

Museum galleries on surveying, ocean knowledge, and maritime science and culture.

Training base for the 2008 Beijing Olympics sailing events.

Yinhai Yacht Club.

The Level Zero Scenic Area sits along the shore of Qingdao Bay. This stretch of waterfront is much quieter compared to the bustling downtown section from Zhanqiao Pier to May Fourth Square. And the coastal scenery is far better. Come see for yourself.