In 1866, on the order of the Tsar, the fortress was closed down and most of its fortifications were demolished.
What remained were cavaliers of Bastions VI and VII and small fragments of other fortifications with gates. The area was still military property, which made complex tidying up very difficult, in spite of many plans to that effect made by the local authorities. During WW I a railway line was built through Zamość, destroying part of the preserved remains of Bastion I in the process. However, the control of post-fortification area north-west of the town centre (remains of Bastion IV and adjacent fragments of fortifications with the moat,
counterguard*, nearby
ravelin* and the preserved caponier) was taken over by the municipality. In 1919-26 an imposing town park was set up on the site in accordance with Walerian Kronenberg’s design; in the park the outline of former fortifications was made clear and was integrated into park landscape. Since most of post-fortification area remained military property for many years, the town developed far from the former fortress, which provided a possibility of preserving its integrity. The Old Town complex and the area of the former fortifications were recognised as historical heritage in July 1936 and after they were taken over by the municipality, their complex preservation started. The 1930s also marked the beginning of historical and conservation research on the former fortress conducted by Professor Jan Zachwatowicz and employees and students of the Department of Architecture of the University of Warsaw. In 1936 an inventory of fortification facilities started to be made. Complex restoration of Zamość, conducted on the basis of act No 139 passed by the Council of Ministers in 1974 started with making a plan of development of the Old Town. At first works were to be done in the Old and New Lubelska Gates, the New and Old Lwowska Gates, Bastion VII and northern and north-western sections of curtain walls. On the recommendation of a scientific consultant J. Kowalczyk, a reconstruction of the Old Lwowska Gate and its ornaments was carried out. The preserved Old Lubelska Gate was supplemented with a bridge leading to the
ravelin*, where an amphitheatre was built (designed by M. Pawlicki). The shape of the former moat was restored and fragments of the
caponier* were uncovered and left as permanent ruin. Part of curtain wall VI –VII and Bastion VII were reconstructed on the basis of results of archaeological research and archive records. Although construction works were not completed as planned till the 400th anniversary of foundation of the town, in 1983 a tourist trail was made available to visitors; it led from the so-called Łukasiński’s Prison Cell by the Old Lwowska Gate through casemates to Bastion VII as far as the
postern* in curtain VI-VII. The Old Lwowska Gate was fitted with a plaque with information about the foundation of Zamość. As a result of incidental discovery of a postern leading to 19th century gate in curtain wall I-II (called Furta Wodna) a passage for pedestrians was made there, leading from the Old Town to the southern fortification foreground. After a break in restoration works during which some reconstructed fortification fragments underwent secondary degradation in 2007 complex research and restoration of both fortification remnants and fortification landscape was resumed.