Review the map showing modern populations of European cities and European physical regions. A untitled map of Europe. The Alpine Mountains are shaded red. The Central Uplands are shaded green. The North European Plain is shaded purple. The Western Uplands is shaded yellow. A key shows populations of 500,000 to 1,000,000, 1,000,001 to 5,000,000, and More than 5,000,000.