Das habe ich hier gefunden: http://www.us-highways.com/us2.htm#US_66
(US 66)
(IL) (MO) (KS) (OK) (TX) (NM) (AZ) (CA) Most of route now posted as Old or Historic 66. US 34 IL-171 I-55 Alt US 66 IL-53 I-55 IL-126 IL-59 I-55 I-270 IL-157 IL-203 IL-111 IL-3 MO-30 MO-366 MO-360 I-44 MO-226 MO-96 Bus 71 MO-66 KS-66 Alt US 69 US 69 US 60 OK-66 US 77 I-44 OK-66 I-40 OK-34 I-40 US 283 I-40 US 60 I-40 (Originally: US 84 I-25 NM-300 NM-466 NM-14 I-25 NM-47 NM-314 NM-6) I-40 AZ-264? US 191? I-40 AZ-66 AZ-95 I-40 I-15 I-215 CA-66 I-210 CA-110 US 101 CA-2
Existed 1926-1985; extended west 1935; Re-aligned in NM 1938; west truncated Pasadena, CA 1964; Topock, AZ 1974; East truncated Gardner, IL 1976; Normal, IL 1978; Scotland, MO 1979; a.k.a.: "Mother Road" and "America's Main Street". US 66 @ Yahoo
Danach gab es die US 66 bis 1985. Einige Staaten waren so nett, die Nr. anschließend beizubehalten.