I use GPS or Google maps. As mentioned by another, parking is limited due to very small lot. Best go on a week day and even better in the off season!
Take Rte 95 North to Rte 128 toward Gloucester. Go around 1st rotary to 2nd exit then 2nd rotary following 128 to the end. Turn left at the light onto 127 take to "5 corners" following signs to Pigeon Cove past train station on Granite past old Tool Company and another mile or so to sign for Halibut State Park. Turn right and parking lot will be on your right. If you get to the Lobster Pool you've gone a little too far. Parking on weekends can be a challenge if you don't get there early
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