Its total length is approximately 10.2 miles (16.4 km).

It was renamed NM 19 in 1940 when US 285 was rerouted through Tres Piedras.

Then in the 1950s it was renamed NM 17 to match Colorado State Highway 17 (SH 17).

This was removed from the state highway system in the 1930s.

[3] Later in the 1950s, NM 40 was used for a highway from Broadview eastward to Hollene.