Budapest of Buda hills are environmentally protected. The city's importance in terms of traffic is very central, because all major European roads and European railway lines lead to Budapest. The Danube was and is still an important water-way and this region in the centre of the Carpathian Basin lies at the cross-roads of trade routes. Budapest is one of only two capital cities in the world which has thermal springs (the other being Reykjavík in Iceland). Some 125 springs produce of thermal water a day, with temperatures ranging up to 58 Celsius. Some of these waters have medicinal effects due to
Budapest terms of the hardiness zone. As per the 1981-2010 climatological norm, widely used in most other European countries, the climate in Budapest has shifted to humid subtropical (Köppen "Cfa"), with averages above 0 °C in the coldest month and above 22 °C in the warmest. Budapest has architecturally noteworthy buildings in a wide range of styles and from distinct time periods, from the ancient times as Roman City of Aquincum in Óbuda (District III), which dates to around 89 AD, to the most modern Palace of Arts, the contemporary arts museum and concert hall. Most buildings in Budapest are relatively