| Madarcos | |
| Settlement Type: | Municipality |
| Mapsize: | 300px |
| Pushpin Label Position: | above |
| Pushpin Mapsize: | 300 |
| Pushpin Map Caption: | Location in Spain |
| Subdivision Type: | Country |
| Subdivision Name: |  Spain |
| Subdivision Type1: | Autonomous community |
| Subdivision Name1: | Community of Madrid |
| Unit Pref: | Imperial |
| Population Blank1 Title: | Ethnicities |
| Utc Offset: | +1 |
| Utc Offset Dst: | +2 |
Madarcos (pronounced as /es/) is a municipality of the Community of Madrid, Spain. It has an area of 8.46 km2 with a population of 49 inhabitants and a density of 5.79 inhabitants / km2 it is the town with the lowest population in the Community of Madrid.[1]
It borders the municipalities of the Sierra Horcajo north and northwest; Horcajuelo of the Sierra and the Rincon Prádena east; Puentes Viejas south, and Gandullas Piñuécar- west. At its end is the desert of La Nava, in the hamlet of the same name, to the southeast of the town, on the edge of the M-137 that connects Buitrago del Lozoya with Montejo de la Sierra, past the turning Madarcos.