| Castillo de las Guardas, El | Sevilla | 41889–41899 | 4 |
| Castillo de Locubín | Jaén | 23670–23693 | 2 |
| Castillo-Albaráñez | Cuenca | 16854 | 1 |
| Castillonroy | Huesca | 22572 | 1 |
| Castillonuevo | Navarra | 31454 | 1 |
| Castilléjar | Granada | 18818 | 1 |
| Castilnuevo | Guadalajara | 19391 | 1 |
| Castraz | Salamanca | 37496 | 1 |
| Castrejón de la Peña | Palencia | 34850–34859 | 3 |
| Castrejón de Trabancos | Valladolid | 47512 | 1 |
| Castrelo de Miño | Ourense | 32430 | 1 |
| Castrelo do Val | Ourense | 32612–32626 | 4 |
| Castril | Granada | 18816 | 1 |
| Castrillo de Cabrera | León | 24742–24744 | 2 |
| Castrillo de Don Juan | Palencia | 34246 | 1 |
| Castrillo de Duero | Valladolid | 47318 | 1 |
| Castrillo de la Guareña | Zamora | 49419 | 1 |
| Castrillo de la Valduerna | León | 24721 | 1 |
| Castrillo de la Vega | Burgos | 09391 | 1 |
| Castrillo de Riopisuerga | Burgos | 09108 | 1 |
| Castrillo de Villavega | Palencia | 34478 | 1 |
| Castrillón | Asturias | 33401–33459 | 7 |
| Castro Caldelas | Ourense | 32760–32794 | 6 |
| Castro de Fuentidueña | Segovia | 40315 | 1 |
| Castro de Rei | Lugo | 27250–27289 | 12 |
| Castro del Río | Córdoba | 14840–14858 | 3 |
| Castro-Urdiales | Cantabria | 39700–39798 | 5 |
| Castrobol | Valladolid | 47689 | 1 |
| Castrocalbón | León | 24760 | 1 |
| Castrocontrigo | León | 24734–24736 | 3 |
| Castrodeza | Valladolid | 47192 | 1 |
| Castrogonzalo | Zamora | 49660 | 1 |
| Castrojeriz | Burgos | 09110 | 1 |
| Castromembibre | Valladolid | 47882 | 1 |
| Castromonte | Valladolid | 47641 | 1 |
| Castronuevo | Zamora | 49127 | 1 |
| Castronuevo de Esgueva | Valladolid | 47171 | 1 |
| Castronuño | Valladolid | 47520 | 1 |
| Castropodame | León | 24314–24398 | 3 |
| Castropol | Asturias | 33760–33794 | 4 |
| Castroponce | Valladolid | 47664 | 1 |
| Castrotierra de Valmadrigal | León | 24323 | 1 |
| Castroverde | Lugo | 27120–27293 | 15 |
| Castroverde de Campos | Zamora | 49110 | 1 |
| Castroverde de Cerrato | Valladolid | 47182 | 1 |
| Castuera | Badajoz | 06420 | 1 |
| Catadau | Valencia | 46196 | 1 |
| Catarroja | Valencia | 46470 | 1 |
| Catoira | Pontevedra | 36612 | 1 |
| Catral | Alicante | 03158 | 1 |
| Catí | Castellón | 12513 | 1 |
| Caudete | Albacete | 02660 | 1 |
| Caudete de las Fuentes | Valencia | 46315 | 1 |
| Caudiel | Castellón | 12440 | 1 |
| Cazalegas | Toledo | 45683 | 1 |
| Cazalilla | Jaén | 23628 | 1 |
| Cazalla de la Sierra | Sevilla | 41370–41730 | 2 |
| Cazorla | Jaén | 23469–23485 | 4 |
| Cazurra | Zamora | 49191 | 1 |
| Cañada | Alicante | 03409 | 1 |