Geography and urban development of Dresden temperatures are almost the same as those in cities in southwest Germany; on average 10.2°C per year. In hot summers, Dresden is between the hot Lusatia and the milder Ore Mountains. Both regions are characterised by strong winters: temperatures of −20°C are not impossible in Dresden. The driest months are February and March, with precipitation of 40 mm. Spring months have often been arid in the last couple of years (with less than 10 mm of precipitation). The most precipitation falls in July and August, at 60 mm per month. Due to its location on the banks of the Elbe
Postage stamps and postal history of Hamburg which belonged to Denmark at that time, was delivered by a Hamburg postal agent, as there was a Hamburg postal agency on Heligoland. On 1 January 1852, Hamburg joined the German-Austrian Postal Union. Since 1866, Hamburg was part of the North German Confederation, which took over the postal service in the North German Postal District on 1 January 1868. The first postage stamps of the Hamburg City Post Office were introduced on 1 January 1859. They were rectangular and in the middle was the coat of arms of the city, overlaid with the value number. Below that is the word