Metres above the Adriatic

Metres above the Adriatic is the vertical datum used in Austria, in the former Yugoslavian states of Slovenia, Croatia, Bosnia-Hercegovina, Serbia, Montenegro, Macedonia, Kosovo, as well as in Albania to measure elevation, referring to the average water level of the Adriatic Sea at the Sartorio mole in the Port of Trieste.

The gauging station in the Port of Trieste was established in the 1875 by the local observatory run by the military geographical institute of the Austro-Hungarian Army. The average water surface elevation at Molo Sartorio became the datum valid for the whole Austro-Hungarian monarchy. Whilst the former Yugoslavian states still use it, the Eastern Bloc successor states of Austria-Hungary like Hungary and Czechoslovakia after World War II switched to the Kronstadt Gauge of the Baltic Sea, which is 0.6747 m higher.

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