[1][2] The salt mine is closed for extraction purposes, but is open for visitors, featuring a microclimate with natural air-conditioning and constant temperature and atmospheric pressure throughout the year.

The same year, engineer Carol Karacsony, the head of the Ocna Dej mine [ro], was appointed to the task.

[4] After geological studies and surveys, Karacsony proposed using the trapezoidal chamber profile method first used in the Wieliczka Salt Mine in Poland.

[citation needed] The mine is composed of 14 chambers with trapezoidal profiles, having a 10 m opening to the ceiling and 32 m to the ground, a height of 54 m and a wall inclination angle of 60 degrees.

[citation needed] Since 1970, the mine has become a tourist attraction, offering exceptional natural conditions as a result of its microclimate, rich in aerosols, which some believe effective in treating Respiratory disease.

The balconies are used for the circulation of the authorized personnel during the periodical inspection of the stability of the surfaces from the superior zone of the mine construction.

[citation needed] Located vertically above the Unirea mine and separated from it by a 40m thick floor, the Mihai level was opened in 1912 and consists of 6 trapezoidal shaped rooms with a 12 m ceiling width, 37 m floor width, 66 m height and a wall inclination angle of 60 degrees.

[citation needed] During the fall of 1994 both levels were severely damaged by the natural phenomenon of salt dissolution due to infiltration of ground and pluvial waters, which flooded the Unirea mine.

The catastrophic aggressiveness of waters flowing down the shaft gradually created huge cavities and the specialists who evaluated the full scope of the disaster decided to close down the mine.

All costs of these works, amounting to a total of over 20 billion Romanian lei (ROL; equivalent to 2 million RON), were exclusively borne by the Slănic salt mine.