Their objective was to explore and map the largely unknown interior from the Vogelkopf in what is now Indonesian West Papua to Samarai.

The chosen means of achieving this was not by foot patrol or aeroplane but by airship.

After some early thought, the Dutch backed out of the project believing it to be too ambitious and too expensive, but the Germans and British continued on schedule for a voyage that would be conducted in 1914.

The airship was to be crewed by a joint team of aviators and would have aboard scientists from both countries.

The expedition would use the most modern airship and mapping technology available at the time.

Graetz crossing a wooden bridge on his drive across Africa,  1907-1909

Leading the mission would be Lieutenant Paul Graetz, a German officer who had famously been the first man to drive across Africa in an automobile.

To promote and help finance the Luftschiff (Airship) Expedition, two stamps were printed.

They were not valid for postage but could be purchased as collectors' items or for use alongside legal postage stamps.

Only the Two Pfennig and One Mark values were produced for sale although proofs of the Two Mark and One Thousand Mark values exist.

The Luftschiff Expedition had to be cancelled due to the outbreak of World War I on 28 July 2014 and the stamps never made it into widespread circulation.

Expedition postcard

The mint stamps are considered extremely rare, and used stamps even more rare. Read more about their philately here.

The only known used copy of the Two Pfennig stamp – called “the Holy Grail of these issues” - was last seen at auction in September 2013 when it sold for €13,500 (K56,000).

A publisher in Berlin also produced postcards advertising the expedition.

Count Ferdinand von Zeppelin (1838–1917), a retired German general who invented the Zeppelin rigid airships and founded the company Luftschiffbau Zeppelin, was approached to help design and build a suitable airship, but thought it impractical.

Ferdinand von Zeppelin

He even wrote to the organisers on 7 June 1913:

“After the scientific preparatory work and experiments that have already been carried out, the feasibility of the best land photos using photogrammetry from long rigid airships cannot be doubted.

“To create a survey of the whole of New Guinea with the help of gas-powered airships, I believe, at least for the time being, to be impracticable because of the coincidence of tropical warmth with mountains 4 to 5,000 meters high. However it is not likely that Lieutenant Graetz will succeed in building a hot air ship suitable for long voyages."

But imagine if such an expedition had taken place.

Not only would it have been one of the greatest technological achievements of the age, the spirit of cooperation engendered at the highest political and scientific levels may even have helped prevent World War I.