I have to agree with tnrvers in that I-68/I-79 vs. I-70/(PA Turnpike)/I-70 will be a pretty much a trade-off of hills vs. fuel savings, free vs. toll roads and open road vs. traffic. Below, I share my knowledge about both routings. Hopefully, it will help in your decision on which way to go. I last traveled on both of these roads between Christmas and New Year's, 2012. I went I-70 east from PA-51 to it's eastern terminus at Baltimore, MD and I-68 west from its eastern terminus at I-70 to exit 14B, (Keysers Ridge) US-40/US-219.
I-70 (via I-68/I-70)
A number of grades on I-68 are in the 7% range. Westbound, you''ll encounter your first challenging grade about 3-4 miles after exiting I-70 west onto I-68 west when you climb Sidling Hill. At the top, just before you pass through a deep cut in the mountain, is a visitor's center. Unfortunately, the visitor's center is closed in winter. I-68 is pretty much a rural, but scenic, route and some exits have limited food/fuel/services. The only sizable town between it's beginning and end is Cumberland, MD. However, be aware that while the speed limit is 65mph, it's reduced to as low as 40mph while passing through the Cumberland, MD area. The I-79 to I-70 part of the ride is unremarkable. The most important thing to be aware of is the hill you decend as you approach the I-70 interchange. The loop at the bottom of the hill for I-70 west is only 25mph. Many trucks have flipped there. Just notice all the scrape marks on the Jersey barrier when you negoiate the loop as evidence. A new ramp is being constructed to eliminate this dangerous condition.
I-70 (via PA Turnpike)
If you decide to take I-70 west, the first long grade you encounter is Town Hill, about 8 miles from the PA state line. The biggest PIA of this route is driving through the town of Breezewood. I-70 ends there and you have to take US-30 east about a half-mile through the town to the PA Turnpike (I-70/I-76) entrance. How long it takes get through Breezewood all depends on the amount of traffic. The steepest grades on the PA Turnpike are only around 2%. The most notable are Allegneny Mountain (about a 7 mile ascent with the Allegheny Tunnel at the top) between Exit 146 (Bedford) & 110 (Somerset). Between Somerset and Exit 91 (Donegal), you climb Laurel Hill (bypass- tunnel eliminated). If you have an E-ZPASS, the PA Turnpike tolls are cheaper than if you pay cash. From PA Turnpike exit 75 (New Stanton) to Washinton PA (where you would reconnect with I-70 west again if you took the I-68/I-79 route), I-70 is a 55mph zone. However, you'll notice that many people still go 65mph (or faster) through this area. To me, this section of I-70 is a poor excuse for an interstate highway. Please be extra careful and alert. Many interchanges lack exit and merge lanes; and if they do have them, they can be extremely short. The ramps at the PA-51 interchange (which I often use) have no merge/exit lanes and have stop signs instead of yield signs. It's a lot of "fun" trying to get 7 tons of truck and trailer from 0 to 55 while in a travel lane (although, it's more like 65-70 the way many people drive it).
I-70: Washington, PA to Ohio
I-70 west becomes a 65mph zone somewhere after you pass through Washington, PA. In WV, it's 70mph until you get close to Wheeling, WV. At exit 10, you'll decend a 2 mile grade, Then, at Wheeling, WV, you have another decision as to whether to stay on I-70 and pass through the city, encounter possible traffic delays, and go through the Wheeling Tunnel or go I-470 around the town but climb over a mountain. Either way, you have a long grade to climb once you cross the Ohio River into OH.
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