West Matukituki Track, Mount Aspiring National Park, New Zealand | 4K 

Amazing and very long walk along West Matukituki River Branch. Rather easy and flat most of the way, gets steeper once you cross the river near French Ridge. Some people choose to do easy, flat parts on bicycles. In summer you should be able to go all the way with dry feet. Offers plenty of amazing views and number of side adventures:
1:36 Rob Roy Track • Rob Roy Glacier Track,...
3:38 Shotover Saddle Route
7:31 Cascade Saddle Track (near Aspiring Hut)
14:21 French Ridge Track
Liverpool track
More info on DOC site: www.doc.govt.nz/parks-and-rec...