It was early in 1913, when the manager of the train station at Gbely reported to Railroad Administration that in the cottage of Ján Medlen, some 30 meters away from the railroad tracks between Gbely and Kúty, a gas explosion occurred. The first ever well was drilled on 28 October 1913 and at 163-168 meters, a reservoir of rare heavy crude oil was found. After successful pumping tests, the Austrian – Hungarian Empire started to produce oil commercially on 13 January 1914. This date is generally considered to be the beginnings of the oil industry in the Slovak territory.
As oil was very precious during the war and its price was continuously rising, 56 successful wells were drilled in Gbely in the following 4 years with an aim to increase production. Thanks to successful exploration, the volume of produced oil increased from 1,631 tons in 1914 to 9,146 tons in 1927. As a result of successful prospecting and intensive opening of new fields during the 50s of the 20th century, the production increased to 60 thousand tons of oil per year.
From the beginning of the 50s, processing of natural gas started, which was considered only a by-product of oil production by then. At that time, in addition to lighting train wagons and its usage in chemistry, it began to be used for household heating. Production of natural gas peaked between 1958 to 1962, when 1.1 - 1.3 bcm was produced annually, until the beginning of the 70s, when 900 - 700 mcm of natural gas was produced annually.
Over 150 years of the development in the Slovak territory, reservoirs with more than 26 bcm of geological stock of natural gas, 3.8 million tons of oil and nearly 0.4 tons of gasoline were found.
So far, approximately 2 860 wells have been drilled in the Vienna Basin and approximately 340 wells in the East Slovakian Basin by NAFTA (including original NAFTA group predecessors).