Wisconsin flying is built around a handful of capable towered airports, then a wide spread of small non-towered public-use fields. The state lists 123 public-use airports, 13 towered airports, 25 with ILS service. KMKE (General Mitchell Intl) is the highest-complexity arrival, with five runways, a 9,990 ft runway, 3 FBOs. Madison and Green Bay give pilots strong IFR alternatives outside Milwaukee. KMSN (Dane County Rgnl/Truax Fld) has a 9,006 ft runway at 887 ft elevation. KGRB (Green Bay/Austin Straubel Intl) has an 8,700 ft runway, 2 FBOs, ILS service. KLSE (La Crosse Rgnl), KEAU (Chippewa Valley Rgnl), KATW (Appleton Intl) add more towered long-runway options across the state. Most Wisconsin flying is still non-towered. That matters for CTAF work, field condition checks, fuel planning, winter operations. The longest runway is not at Milwaukee. It is the 12,000 ft runway at KEZS (Shawano Muni). The highest listed field is KLNL (Kings Land O' Lakes) at 1,706 ft, so northern Wisconsin can bring performance considerations even without mountain terrain.