C
| Ancient name | Location | Modern name | Also known as |
| Cebrene | Troad region of Turkey | Kebrene, Kevrin, Alexandria (Greek: Αλεξάνδρεια), Antiochia in Troad (Greek: Αντιόχεια της Τρωάδας) | |
| Chalcedon | opposite Byzantium, south of Scutari (modern Üsküdar) | Kadıköy | Chalkedon, Calchedon (Καλχήδων) |
| Calydon | Aetolia, Greece | ||
| Carystus | near modern Karystos, Euboea, Greece | ||
| Chamaizi | Crete, Greece | ||
| Chalcis | Euboea, Greece | Chalkida, Halkida, Halkis, Chalkis | |
| Chersonesos | near Sevastopol, Crimea | Korsun, Khersones, Chersonese, Chersonesos, Cherson | |
| Chytri | Cyprus | Kythrea | Chytroi (Χύτροι) |
| Clazomenae | near İzmir, in Turkey | Kilizman | Clazomenae (Κλαζομεναί) |
| Cnidus | situated on Datça peninsula, southwestern Turkey | Tekir | Knidos (Κνίδος) |
| Colosse | Phrygia, Asia Minor (modern Turkey) | abandoned | Κολλοσσαί, Colossae, Chonae, Kona |
| Corcyra | Corfu island, Greece | Corfu | Κέρκυρα, Κόρκυρα, Corcyra, Corfu, Corfù, Kérkyra |
| Corcyra Melaena | Korčula island, Dalmatia (part of modern Croatia) | Korčula | Κόρκυρα Μέλαινα, Kórkyra Mélaina, Corcyra Nigra |
| Corcyra (Mesopotamia) | Kirkuk Gοvernorate, Mesopotamia (modern Iraq) | Kirkuk | Kórkura, Kirkoúk |
| Corinth | Isthmus of Corinth, Greece | Korinth, Acrocorinth, Korinthos, Ephyra | |
| Croton | Calabria, southern Italy | Crotone | Crotona, Cotrone |
| Cumae | northwest of Naples | abandoned | Cuma (Κύμη or Κύμαι) |
| Cyme | Aeolis, Turkey | Namurt | Kymi, Phriconis |
| Cyrene | near Shahhat, Cyrenaica, Libya | abandoned | |
| Cythera | Ionian Islands, Greece |
Read more about this topic: List Of Ancient Greek Cities