Alcalá de Henares is a Spanish city in the Community of Madrid. Straddling the Henares River, it is located 31 kilometres to the northeast of the center of Madrid. As of 2018, it has a population of 193,751, making it the region's third-most populated municipality. Predated by earlier settlements on the left bank of the Henares, the city has its origins in the Complutum settlement founded in Roman times on the right bank of the river, that became a bishopric seat in the 5th century.