Mon-Sun 9:00 am - 5:00 pm from early May - late October
You can drive in any time to the Lighthouse. During the time the front booth is open it costs $3 per person. After hours it's free. Granted the buildings are not open but the view is ;)
Even when the park is open there are times the lighthouse isn't open for climbing. If you just want photos you can get on the grounds most anytime. I have photos of the lighthouse park posted in a review here. Check it out! By the way, the grounds are maintained by the town of Bristol, Maine. Their website or chamber of commerce may be able to give you mote information.
Check the website for details on hours of operation.
Closed at 5 in September.
I am not sure how early it is open but it closes at 4pm. I would check locally, maybe with a chamber of commerce to find out if it is open all year or not.
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