Budapest is the capital and largest city of Hungary. It was made as such in 1873. In that year, three towns on the River Danube, namely Buda, Óbuda (Old Buda) and Pest were united. About 1.7 million people live in the city. Its highest place is János Hill (527 m). Budapest has a humid subtropical climate with relatively cold winters and quite warm summers.[10] Celtic tribes lived there before 1 AD. Later, the Roman Empire transformed the first settlements into the Roman town of Aquincum. The Hungarians arrived in the territory of modern Hungary only at the end of 9th century AD.