Born in Hulerød, Hammer was the son of District Commissioner and Inspector Frederik Abel Hammer (d. 1877) and Elisabeth Kirstine Lemvigh (1794–1849).
Halifax Regional Municipality | Oeiras Municipality, Portugal | Municipality | Solna Municipality | Copenhagen Municipality | Stockholm Municipality | Municipality of Mosman | Garmen Municipality | Municipality of Lane Cove | José Félix Ribas Municipality, Aragua | Alenquer Municipality, Portugal | Tran Municipality | Struga Municipality | Regional Municipality of Waterloo | Regional Municipality of Niagara | Maia Municipality | Luanda Municipality | Krushari Municipality | Kičevo Municipality | Gothenburg Municipality | General Toshevo Municipality | Frederiksberg Municipality | Ekurhuleni Metropolitan Municipality | City of Tshwane Metropolitan Municipality | Centar Municipality, Sarajevo | Cape Winelands District Municipality | Caniapiscau Regional County Municipality | West Rand District Municipality | West Coast District Municipality | Veles Municipality |