 The treacherous nature of these waters, however, also convinced Roze that any movement against the fortified Korean capital with his limited numbers and large hulled vessels was impossible.Instead, he opted to seize and occupy Ganghwa Island, which commanded the entrance to the Han River, in the hopes of blockading the waterway to the capital during the important harvest season and thus forcing demands and reparations on the Korean court.The nature that these demands were to take was never fully determined.