1900s	1910s	1920s	1930s	1940s	1950s	1960s	1970s	1980s	1990s	2000s

1911
Nation's first centerline on River Road near Trenton painted by the Wayne County Road Commission - considered one of the most important safety devices in the history of auto transportation (in 1917, the first centerline on a state highway)

1912
First Highway Department to establish a testing laboratory

1917
First "crow's nest" traffic signal tower erected in Detroit (Woodward at Michigan)

1919
Approval of first state bond program for highways leading to a five-year construction program that produces 3,600 miles of state highway

1919
The nation's first roadside park along US-2 in Iron County