Archaeological excavations at the site of Yenikapı, the most important main station for Metro and Marmaray projects on the European side of İstanbul, were started in 2004 with the discovery of numerous shipwrecks, amphorae, and skeletal remains belonging to animals. The findings from the excavations conducted by the İstanbul Archaeological Museums of the General Directorate of Cultural Heritage and Museums proved that this site, known in the Ottoman period as Langa Bostanları , was actually the ancient harbor of Theodosius. The archeological material and animal skeletal residues, mostly of horse origin, were found side by side in excavations initiated in 2004 and covering an area over 58,000 m2. Horse (Equus caballus L.) skeletons were the most numerous, reaching 32.64%, and were followed by cattle, sheep, and pigs, which had been used for consumption. A brief preevaluation has been established by determining the pathologies, butchery marks, and modifications on approximately 34 animal species bones in the present study.