Thanks QT, that is a much better map showing that by taking Highway 5 you can get there pretty fast. My guess is that if she was killed by Zodiac, he probably flew back and forth to California rather than drive each time, in order for him to be at the painting party ,being seen watching Darlene at Terry's and then killing Darlene July 69.
He might have had relatives or friends living in or near Albany, to give him access to a car.
It is very rare for a serial killer to kill out of his comfort zone,so he was probably familiar with Albany.
I do believe that Zodiac spent time in NY especially after his July 1974 letter, when he was silent until April 1978. I personally believe along with Sherwood Morrill ,that the 78 letter was genuine and that he was giving us what he felt was a fair warning that he was back.
That is something that my POi has done in the past, he will usually let me know when he is in town.
Once shortly after I had moved in the early 70's, he called to say" I just want you to know, I know where you live".