Effective January 1, 2012, Styria merged the districts of Judenburg and Knittelfeld to form the Murtal district. The merger was part of program aimed at streamlining the regional bureaucracy. On January 1, 2013, three more mergers followed: Bruck was merged with Mürzzuschlag, Hartberg with Fürstenfeld, and Feldbach with Radkersburg.[18] Effective January 1, 2017, Lower Austria split the districts of Wien-Umgebung into parts which were merged with the districts of Bruck an der Leitha, Korneuburg, Sankt Pölten and Tulln respectively.
来自:
https://en.wikipedia.org/wiki/District_(Austria)