 It runs through Oshkosh as Main Street, then turns onto Algoma Boulevard, which it follows out of Oshkosh.As it crosses I-41 it becomes a freeway facility to US 10 in Winchester.After briefly joining US 10, US 45 takes a northward track as a two-lane rural road and heads into North Central Wisconsin with the exception of a four-lane expressway between Clintonville and Marion.