What is the most times a interstate has had permament speed limit changes?

[SteveG1988]

I'm not talking about due to construction, or similar. But when the speed limit was 24/7 lowered for 365 days a year by legislature, where it is xx mph on this road before any construction.

[hotdogPi]

One, by the definition of permanent.

[wriddle082]

I would think most freeways built in rural areas outside the Northeast before 1973 have had at least one reduction from whatever they were posted at down to 55.  Then most were raised to 65 around 1985 or 1986.  Then after 1996 many were raised to 70 and a few to 75.

[hbelkins]

Kentucky went 70-55-65-70.

[cl94]

Are we counting the New York Thruway or Pennsylvania Turnpike before the Interstate designation was applied? Both have had a ton. IIRC, the Thruway has been 55, 60, 65, and 70 at different points in time, most of which were post-1957.

[noelbotevera]

If we count the PA Turnpike, it went from no speed limit (but the tunnels had a 35 mph, but I won't count it), to 70 (1940-1941 at the beginning of World War II), to 35 (1941-1942), 70 (1942-1956), 65 (1956 to the NMSL, 1974), 55 (1974 to the end of the NMSL in 1995, House Bill #213), 65/55 ( House Bill #213 1995-2005), 65 (2005-2014), 70 (2014-)

That's a total of 9 changes in speed limits.

[SteveG1988]

If we count the PA Turnpike, it went from no speed limit (but the tunnels had a 35 mph, but I won't count it), to 70 (1940-1941 at the beginning of World War II), to 35 (1941-1942), 70 (1942-1956), 65 (1956 to the NMSL, 1974), 55 (1974 to the end of the NMSL in 1995, House Bill #213), 65/55 ( House Bill #213 1995-2005), 65 (2005-2014), 70 (2014-)

That's a total of 9 changes in speed limits.

That's the definition of Permament i was looking for.

[bzakharin]

Were the interstates in the Philadelphia area (I-95 throughout PA and Delaware, the Schuylkill Expressway, the Blue Route section of I-476, I-295 between exits 26 and 36, I-676 in NJ)ever above 55?

[PHLBOS]

Were the interstates in the Philadelphia area (I-95 throughout PA and Delaware, the Schuylkill Expressway, the Blue Route section of I-476, I-295 between exits 26 and 36, I-676 in NJ)ever above 55?

The first segment of the I-476/Blue Route opened years after (1979) the 55 NSL took effect; similar could be said for the stretch of I-95 from Penns Landing to just beyond the airport (Exit 10).

[peterj920]

Starting in the 1970s, I-94 in Southern Milwaukee County was 55.  It was raised to 65, then lowered to 55.  A new sheriff was elected and it was raised to 65 again.  Now it is at 70.