Dealing with the Kiel end of the canal first, the entrance is situated some seven or eight miles up the estuary leading into Kiel Bay. From Kiel Bay to the North Sea a vessel has, according to her draught of water, the choice of three routes into the Kattegat, viz., Little Belt, Great Belt and the Sound. The first-named could only be used by small light draught vessels, such as destroyers and submarines. The passage through the Great Belt, and also that via the Sound, would have to be navigated by a heavy battleship on a favourable state of the tide. The least width across the Little Belt is abreast of the town of Fredericia, in Denmark, where the passage is less than three-quarters of a mile wide. In the Great Belt the navigable channels are restricted in places to about a mile or even less in width. Between Helsingor, in Denmark, and Helsinborg, in Sweden, the Sound is but little over a mile wide and only about 20 ft. deep at low water. The eastern channel of the Kattegat has deep water, and the distance between the Scaw, the northern end of Denmark, and the nearest outlying island off the Swedish coast, is about twenty-five miles. From the above showing, it will be seen that the narrow and tortuous passages which a warship must use if she wishes to proceed from Kiel Bay to the North Sea present an easy problem to render them unnavigable by the use of submarine mines. And, again, the narrowness of the entrance to the Kattegat lends itself to easy watching by the scouts of a fleet in the North Sea. German naval authorities, of course, realised the geographical disadvantages of Kiel years ago, and, in an attempt to remedy the evil, widened and deepened the Kiel Canal. The Elbe entrance of the canal, which is situated at Brunsbüttel, is some seventeen miles from Cuxhaven, which, as is well known, is the Gravesend of Hamburg. The channels between Brunsbüttel and Cuxhaven, which are very narrow, have a sufficient depth at low water for vessels of a moderate draught, and the anchorage room, except for ships drawing but a few feet of water, is somewhat limited. A big battleship, drawing 30 ft. or more, as she would do with stores and ammunition on board, would have to navigate the distance from the canal entrance to Cuxhaven on a flood tide, and if required to bring up would have to moor in the usual manner with two anchors. In fact, the same navigational procedure would have to be followed after passing Cuxhaven until the ship would nearly reach No. 2 Lightship at the mouth of the Elbe.