Kansas replaced the US-66 designation with K-66 on the portion of historic highway not numbered as US-69 Alt.

Shortly past this intersection, K-66 becomes a four-lane divided highway and then crosses the Spring River.

It remains a divided highway for roughly 2.5 miles (4.0 km) then converts back to two-lane, and shortly later intersects the northern terminus of K-26 (South Main Street).

Original US-66 through Kansas continues as a county road to the north and west of US-69 Alt.

The 13 miles (21 km) of US-66 in Kansas retain much of the character of the Mother Road.