The association offers two launches, one to Thacher Island Lights and another to Straitsmouth Island Lighthouse. Note that on the way to Thatcher Island, you will also pass Straitsmouth Island Lighthouse. Trips are limited to 6 passengers. Passport stamps for the lighthouses are provided on Thacher Island. Trips leave from: T-wharf, Rockport, MA 01966. Please see the website for specific dates and times of all excursions. 617-599-2590.