Two mountain ranges traverse the island from east to west; the highest point is Mt. Olympus (6,406 ft/1,953 m), in the southwest. Between the ranges lies a wide plain, the chief agricultural region. Since the 1970s, diminished rainfall and increased population and economic growth have reduced local water supplies. Over three quarters of the population is Greek, generally residing in the southern sector of the country, and belongs to the Greek Orthodox Church. Less than 20% of the people are Turkish Muslims, mainly living in the northern region. Religious minorities include the Maronites and Armenian Orthodox. In addition to Greek and Turkish, English is also widely spoken.