The study was conducted within the project Hidden Stories of the Republic of Moldova. The urban underground and its use during the Soviet period in order to investigate the built heritage of the underground area of Soroca. We conducted field investigations that resulted in the successful identification, repertory and research of 16 underground constructions, one of them, located in the citadel park, being discovered and researched archaeologically. The constructions have different purposes such as warehouses, commercial, industrial, aqueduct system and transport systems, constructions for leisure. The results of the research of the underground architectural heritage contributed with new information on the history of the city, the architectural development, the economic activities and the social life of the past centuries in the old city on the Dniester river.