Imenski rov (Rov starih podpisov), the Old Cave (Stara jama), was the only part of Postojnska jama known for several centuries until 1818 when Luka Čeč discovered the access to the inner parts of the cave. Here we documented ca. 400 inscriptions. About 100 more were also recorded in the historic part of Predjama Cave. From these signatures we correlated 19 with independently historically known persons, less than 5% of the total. The correlation is firm for 15 names, but only tentative for Bellegarde, Kotze, Mihanović and Karl von Zur. The oldest one is that of Johann Melchior Ott(o) of 1642, a painter in the service of Johann Anton zu Eggenberg (1610–1649) the owner of the Castle of Adelsberg at the time, whose coat of arms Ott drew as well. The next oldest is the name Josef Anton Nagel 1748 who also left Latin inscriptions in Predjama cave and in Sloup Cavern, Moravia. All other inscriptions of historic persons are younger than 1800 including those of Franz Graf von Hohenwart, Joseph Petsch Ritter von Löwengreif and Alois Schaffenrath (each with several inscriptions). Noteworthy are also the signatures of Josef Franz Eggenhöfner (1801 or 1809, and 1820; developer of Grotta di Padriciano), Johann Natterer (biologist, 1815, who stayed 19 years in Brazil and laid the basis of the zoological department of the Natural History Museum in Vienna), Karl Beyrich (1819, botanist who died during an expedition in Arkansas, 1834), Giuseppe de Volpi (1820, from Trieste who published first evidence of the cave bear presence in Postojnska jama), Johann Fercher, mine supervisor, and his team of miners from Idrija who signed during their survey of the cave in 1833, Johann Ritter von Hauer (1836 in Pisani rov, Vienna, Imperial Councelor of War and Palaeontologist), Ivan Andrej Perko (the later director of the cave) and several cave guides. Members of the nobility or state employees include Bellegard, Adrienne Brandis Desenffans and her brother Karl Graf Desenffans, Carl von Kotze, and Mihanović.