This article has systematized the experience in research of mediaeval historical and archaeological monuments located in the modern village of Pionerskoe near Simferopol, primarily Eski-Dzhami mosque and the ruins of, presumably, caravanserai. The current stage of research produced numerous hypotheses, often contradicting each other and based both on scientific facts and on groundless guesses. This study is aimed at the elimination of the gaps in the history of research of the said objects from the last quarter of the eighteenth century on. It widely uses the writings of many travellers who visited the Crimean Peninsula both for personal reasons and by office duty (A. N. Demidov, F. Dubois de Montpereux, Ch. Montandon, P. S. Pallas, P. I. Sumarokov, and others), and also academic publications by Russian researchers of ancient monuments (B. N. Zasypkin, E. D. Zilivinskaia, V. P. Kirilko, A. L. Iakobson, and others). Historical sources from earlier period (the works of Evliya Çelebi and others) and materials from the map collection of the A. Kh. Steven Taurica Scholarly Library at the Central Museum of the Taurida (Simferopol) are also attracted. The main stages of the research of the monuments have been determined, and the experience of monument identification in the Russian scholarship has been summarized. The first attempts to preserve and protect architectural sites related to the works of the Taurida Scholarly Archival Commission in the late-nineteenth century have been characterized. The experience of archaeological research of the mosque has been presented.