The dockyards occupy a vast eighty-acre site about a mile north of the town centre along the Dock Road; it's a not very pleasant fifteen-minute walk from Chatham town centre, or a short ride on the bus (ask at Rochester's tourist office for the latest timetable). Behind the stern brick wall you'll find an array of historically and architecturally fascinating buildings dating back to the early eighteenth century. In addition to an impressive display of fifteen historic RNLI lifeboats, there's the "Wooden Walls" gallery , where you can experience life as an apprentice in the eighteenth-century dockyards. Here, too, lies the Ocelot Submarine , the last warship built, at Chatham, whose crew endured unbelievably cramped conditions, a major deterrent to visiting claustrophobes. The main part of the exhibition, however, consists of the Ropery complex , including the former rope-making room - at a quarter of a mile long, it's the longest room in the country.