Starting from southern RI is the Watch Hill light with a nice beach below. Travel RT. 1A toward Narragansett to the Point Judith light. Watch the surfers on the point and listen to the waves crash on the rocky shore. Go north up RT. 1A, across the Jamestown bridge and explore this small island. There is a very nice light here and I can not think of it's name. Next to the lighthouse is a great little museum of sorts, on lights in the area. The lighhouse sits atop a rock cliff with a nice view of the Bay. Also on Jamestown is an old fort, if you like to explore. The grounds around the fort have great views of Newport. I don't recall any lighhouses in Newport, but at least take the senic drive(it's like a loop) past the mansions, newer homes along the shore, and the old Kennedy estate. Another beautiful ride is to the Sackonnet light on the eastern side of the state. Somewhere in the area is the Sakonnet Vineyards. And lets not forget the Block Island Lighthouse on beautiful Block Island, which you will have to take a ferry to get to. Cars are allowed on this ferry. There is another lighhouse in Warwick Neck, at the end of Warwick Neck Ave., but it is gated with no access.

I am not sure if any of the lights are open to the public. If you are thinking of going I would get in touch with the state tourism department to better plan your visit. If I missed anything I hope someone will comment.