Siedlce is located in the eastern part of the Masovian Province on the traditional international route running almost all of Europe from Lisbon through Paris, Berlin to Moscow. The international railway line going through the city connects the east and west of Europe.
Siedlce is in the transitional climate zone with predominant continental climate influences. Average summer temperatures range from 12.2 ° C to 23.9 ° C. In winter they are from -4 ° C to 1.2 ° C respectively. The average an nual rainfall in Siedlce is 522 mml.