I-475 Georgia (link)
15.83 miles ; bypasses Macon to the west. True road geeks do not
take this road, as they would miss seeing I-16. Opened between 1965 and
See also: Interstate Guide: I-475 (AARoads)
I-475 (cancelled) Georgia (link)
Another dead Atlanta freeway (the number is now used for the Macon bypass).
I-475 was to run from I-75/85 along what is now GA 10 (Freedom Parkway), US 78,
and the Stone Mountain Fwy (GA 410) to I-285.
Somehow the dead I-420 would also hook up with
I-475, probably near Decatur. 
The Stone Mountain Tollway (maybe related to I-475) was planned in 1961 but killed
in 1972 by Gov. Jimmy Carter. GaDOT revived it in 1978 as a parkway but it met strong
opposition again and was killed. (This project actually suffered the indignity of
having a protester chain himself to a tree in the bulldozer's path.)
20.37 miles ; from I-75 in Perrysburg to I-75 in Toledo. Part of this is
co-signed with US 23, which further south may become I-73. I-475 was completed
in 1972. 
I-475 Michigan (link)
16.99 miles ; eastern loop of I-75 serving Michael Moore's hometown, Flint.
Finished in 1981.  It's called the United Auto Workers Freeway. 
In 1958, Michigan wanted to call this Interstate 175. 
See also: Interstate Guide: I-475 (AARoads)
I-475 (proposed) Tennessee (link)
Route 475 is the Knoxville Parkway, a planned 28-mile route from I-40/I-75 west of
Knoxville to I-75 north of the city. As with "I-840" around Nashville,
TDOT is using a state route designation. Given the particular number chosen,
and the allure of the Interstate marker for business and tourism, a future
Interstate designation cannot be ruled out.
As of June 2006, TDOT has approved the recommendations of the Regional
Parkway Design Resource Team. Route 475 would have these features: 
- Four-lane freeway, with 12-foot travel lanes, 12-foot outside
shoulders, and a 52-foot depressed median
- Interchanges at Pellissippi Parkway (TN 162), Clinton* Highway (US
25W), and both ends at I-75. (Are these the only interchanges?)
- 70 mph design speed (posted speed is TBD)
- seek a Scenic or Tennessee Parkway designation to prohibit billboards.
Over time, the proposed highway's name has changed from "Beltway" to "Parkway."
The Knoxville Beltway corridor was identified as a potential future need in the
mid-1970s; a traffic and route survey were completed in 1977. 
The idea lay dormant for 20 years, possibly waiting until traffic needs caught
up with projections.
In the late 1990s, the idea was revived, with 3 alternative routes:
  
- "Blue" route, 40.2 miles, from I-75 near Lenoir City to
I-75 by the Clinch River near Lake City; $411 million
- "Orange" route, 24 miles, from I-40/75 to I-75 between Raccoon
Valley Road and TN Highway 61; $273 million; includes possible upgrades
to 13 miles of I-40 and I-75
- "Green" route, 29 miles, from I-40/75 near TN 131 due north to
intercept the Orange route; $223 million; includes possible upgrades to
13 miles of I-40 and I-75
An earlier alternative, a modified 16-mile Orange Route to address
Hardin Valley opposition, would have used Pellissippi Parkway
to connect to Interstates 40 and 75. 
The Winner Is... the Orange Route
Public hearings on the route selection were held in Feb. 2002, and the
Orange Route was selected in July.   (A 2003 TDOT
press release says August, which is close enough.)
The announcement was greeted with boos, insults, and charges of "Liar!"
toward Transportation Commissioner Bruce Saltsman. 
Delay in 2003; project under review
In January 2003, TDOT officials halted work on Route 475 until incoming Gov.
Phil Bredesen could review the project; this review was part of his campaign
In February 2003, new TDOT commissioner Gerald Nicely initiated a
four-month review of 15 state projects totaling nearly $2 billion, a
move intended to help restore public confidence in the agency. Projects
underway, including Route 475, were put on hold during the review.
 In early 2003, preliminary engineering work began. 
The Modified "Orange Route"
In November 2003, TDOT Commissioner Nicely said the $270 million Route
475 project was approved, using the modified Orange Route selected in
August (or July) 2002. Studies and public hearings would delay the start
of construction by about 3 to 5 years. 
The project endpoints do not coincide with the endpoints of new construction,
because it overlaps with I-75 at both ends. The project endpoints are:
- west: I-75 near Lenoir City, 5.8 miles SW of the I-40/I-75 merge
- east: I-75, 3 miles north of TN 61
But the physical endpoints of the new Route 475 are:
- west: very close to or at the I-75/I-40 split
- east: I-75, between Hwy 170 and Hwy 131
At the western overlap, I-75 would be widened to six lanes. No widening
is proposed for the eastern overlap. The new highway, about 24.4 miles
long, would have seven interchanges. The total length including overlaps
is 36.5 miles. [18
Extension eastward to I-40?
now has used to have the Route map online, giving a regional
view of where I-475 might go. The interesting part is was an added green
corridor marking (not labeled) extending to I-40 near TN 139. This could
be an intended eastward extension of Route 475.  (Another telling
indicator was TDOT's use of "Beltway" rather than "Bypass" for the route; but now
its moniker is "Parkway.")
* probably not Hillary
- Route Log and Finder List - Interstate Highways, FHWA, Oct. 31, 2002.
- Johnson, Kevin. "Proposed I-475 around Knoxville, TN." Personal email, April 12, 1997.
- King, Michael. "Atlanta Interstate Development.." Online posting, misc.transport.road, Feb. 7, 1996.
- Jim K. Georges. 'More GA 3di Info.' Personal email, Jan. 31, 1998.
- Johnson, Kevin. "More Info on proposed I-475 around Knoxville." Personal email, April 13, 1997.
- "Beltway blues: NIMBY rules." Knoxville News-Sentinel Feb. 14, 1999.
- Connolly, Brian. "I-475 in Michigan." Personal email, June 20, 2002.
- Knoxville Beltway - Route 475. Tennessee DOT.
- Peacock, Bobby. "Nitpick about MI 475." Personal email, June 20, 2001.
- Napier, Jeffrey. "I-475 in Tennessee- Update." Personal email, Feb. 3, 2002.
- "Recommended Numbering, Interstate Highways in Michigan." Michigan State Highway Department, April 25, 1958. Thanks to Stephen Summers.
- "Dissent greets beltway decision: Transportation chief says 'no choice' but Orange Route." Knoxville News Sentinel, Aug. 1, 2002 (thanks to Jeffrey Napier)
- Napier, Jeffrey. "I-475: Maybe to Sevierville???" Personal email, Aug. 1, 2002.
- Simpson, John. "Route 475." Ohio Highways. http://pages.prodigy.net/john.simpson/highways/475.html (6 Aug 2002).
- "Orange Route gets red light until review." Knoxville News-Sentinel, Jan. 9, 2003.
- "TDOT to take second look at projects." Nashville Tennesseean, Feb. 16, 2003. (thanks to John Lansford)
- "Beltway OK'd: Orange Route needed, says state highway chief; Pellissippi extension, too." Knoxville News-Sentinel, Nov. 11, 2003.
- Tennessee Department of Transportation. "TDOT Announces Decision on Knoxville Beltway Project." Nov. 10, 2003.
- Tennessee Department of Transportation. "Knoxville Parkway Citizens Team Recommendations are Accepted; Governor and Commissioner ready to move project forward." Press release, Nov. 10, 2003.