Button copy freeway entrance signs?

[jrouse]

I don't remember ever seeing a 'Freeway Entrance' sign itself in button-copy. 

I found it interesting that the I-605 shield is considerably larger than the I-210 shield.  My guess is that since the 605 main starting point is at this intersection, that is why the I-605 shield is larger.

At one point in time the I-605 designation stopped at I-10 and it was to be a state route north of there (Route 243). So I was wondering if perhaps that shield was covering a state route shield. But that wouldn't be possible. The I-605 designation was extended north of I-10 in 1968, but the I-605/I-210 junction was built in 1971. 

[kphoger]

Re:  freeway entrance signs in other states...

I guess I was thinking specifically of the California standard sign, and wasn't even considering other freeway entrance signage.

I usually consider the prohibition signs to be the official starting point of the freeway.  You know–motorized vehicles only, no hitchhiking, no U turns, etc.  I never paid close attention until I started hitchhiking, but then it became important:  walking past that sign to hitchhike was a violation of the law (assuming it said "no hitchhiking), while standing in front of the sign left the legality up to any applicable state and local laws.

Even those prohibition signs seem to be absent from many (all?) freeways in Missouri.  What other states out there don't post any type of freeway entrance or prohibition signs?

[NE2]

Even those prohibition signs seem to be absent from many (all?) freeways in Missouri.

I don't think Missouri has a blanket prohibition on bikes/peds on Interstates. At least one sign does exist: http://maps.google.com/maps?hl=en&ll=39.100742,-94.571482&spn=0.007427,0.016512&gl=us&t=m&z=17&layer=c&cbll=39.100748,-94.571595&panoid=5j3_dwcJlLq5ZuLg8DTBEw&cbp=12,315.19,,1,0.13