Excavations at Kelenderis, an ancient port city in the mountainous Cilicia region of Aydıncık district in Mersin province, began in 1986. The first phase of excavations, between 1986 and 2020, was led by Prof. Dr. K. Levent Zoroğlu. Each season lasted approximately 2-3 months, and excavations were carried out in the eastern, western, and northern necropolises. The harbor baths and agora basilica were excavated and restored. The odeon and harbor mosaic were excavated in the second phase, but their completion was later. Prof. Dr. K. Levent Zoroğlu published numerous articles and a book titled "Kelenderis I" in 1994 regarding these studies.Since 2021, excavations have been conducted by Assoc. Prof. Dr. Mahmut Aydın, a faculty member of the Archaeology Department at Batman University, on behalf of the Ministry of Culture and Tourism and Batman University. Excavation, conservation, and documentation work continued for 12 months throughout the year. During the 2021-2025 excavation, conservation, documentation, and research period, the excavation of the odeon, the harbor mosaic, the medieval city walls, and the harbor structures was completed. Conservation work was carried out in all excavated areas. Furthermore, excavation and landscaping work was initiated and is ongoing in the acropolis."Kelenderis II: 2021-2025" is the second book on Kelenderis, covering the aforementioned five-year period of work. The book includes articles on the conservation work of the harbor mosaic, the odeon, and the medieval city walls; the mosaics and architecture of the basilica-plan church; and the conservation work of the harbor baths. It also includes articles on the results of archaeometric analysis of glass mosaic fragments from the basilica-plan church, window panes from the odeon, and metal artifacts related to fishing. Other research materials included in this book are the excavation of the harbor structures, seals recovered from these structures, the bull figure, the Kelenderis Hecate, Kelenderis coins, and the Serapis inscription.We would like to thank the Ministry of Culture and Tourism, the General Directorate of Cultural Heritage and Museums, the Department of Excavations and Research, the Department of Heritage for the Future, and the Rectorate of Batman University for their support at every stage of our excavation work carried out between 2021 and 2025.The main economic supporter of our excavation and conservation work is undoubtedly the Ministry of Culture and Tourism. In addition to the Ministry, the Turkish Historical Society, Mersin Metropolitan Municipality, Aydıncık Municipality, and Batman University have also provided financial support to our excavations and contributed to the provision of personnel and materials. In addition to these institutions, we would also like to thank Takı Art LMT ŞTİ for their partial support in the printing of this book.The final proofreading of the book was done by Assoc. Prof. Dr. Bilcan GÖKÇE. We would like to extend our thanks to Prof. Dr. Bilcan GÖKÇE and Assoc. Prof. Dr. Esra Kaçmaz LEVENT. Our final thanks go to our families who supported us throughout the excavation work and never left us alone when we needed them. We also thank Prof. Dr. [Name], who handed over the Kelenderis excavation to the new excavation director and never left us alone. We are also grateful to K. Levent ZOROĞLU.We hope this book, covering excavation, restoration, and research works between 2021 and 2025, will be useful to you.