Original: While not part of the system 's early plans , the turnpike was eventually incorporated into the Interstate system in late 1956 , and is designated today as four different Interstate Highway routes : I-35 , I-335 , I-470 , and I-70 .
Simplified: However , it became part of the system in 1956 . Parts of the turnpike also are parts of four Interstate Highways : I-35 , I-335 , I-470 , and I-70 .