For some reason, lighthouses make for good adventures and this one is set up to provide an ideal location. It's on a small island, which you can situate in an appropriate place - marking reefs, or the approaches to a harbour or warning of cliffs - in your campaign world. The first plan provides the entire island, complete with a dock, a small warehouse beside it, and some mysterious ruins as well as the building that provides the lighthouse itself and living quarters for its keepers.
The second plan shows how the island is riddled with caves which interconnect all the structures on the island. Excellent for locating a pirate base, or hiding fugitives plotting against unjust rulers... you see, just looking at these plans spawns ideas for how to use them!
The third plan depicts the lighthouse building itself. It has 2 stories, being quite generous living quarters for the lighthouse-keepers, with a tower at one side to hold the light which stands three of stories higher. There's also a high chamber suitable for keeping a lookout. It's a quite substantial building and would make a nice if isolated home. A side elevation is provided to help you get the picture, before we move on to a plan of the ruined building and the cellars beneath (which connect to the underground caverns, of course).
All plans are presented in black and white or in blue, and are to some measure customisable - you can turn off grid lines, numbering, and furniture (where present). Several pages are provided for you to make notes, but you'll have to print them out to scribble on unless you have a very steady hand at adding text to Acrobat pages!
It all makes for a good base for pirates or anyone who likes the isolation, or indeed if you actually need a lighthouse and the action goes there. With this plan to hand, it probably will!