That was one of the interstates we traveled! From where ever it intersects this smallish country  road just on the Illinois side, we had to get off the 64 since it is closed in St. Louis.  The Mississippi was still behaving back in May when we went through.  One of the highlights was seeing the Gateway Arch, my Dad was raised in the St. Louis area, we traveled to visit a couple times when I was growing up.  I was about 6 yrs. old when we went up in the Arch, I sort of remember it, it was very small.  I hadn't done the research to figure if we would pass by it or not, so we said nothing to the children, it was a really fun surprise for all of us, when my husband spotted the top peeking over a hill!

We were only on the 70 until Columbia, then we headed north to LaPlata, it was a short time, but I remember it because I thought we would never get out of St. Louis and its suburbs!  And it was pretty boring!