Topography
IWAKUNI/KURE
TOPOGRAPHY
Hiroshima Bay is that portion of the Inland Sea of Japan associated with the city of Hiroshima.
As seen in Figure 1, Figure 2, Figure 3, and Figure 4, Iwakuni is located on the western side of the bay in a relatively flat, open area while Kure is embedded in a region of mountains and mountainous islands with almost complete protection from all directions. Yashiro Island, located in south Hiroshima Bay, and the numerous smaller islands offer effective barriers to winds and seas from the south. They also are responsible for the almost negligible surge and relatively moderate seas in the bay with southerly winds. The lee side of any of the larger islands in the bay area provides substantial protection from both wind and sea. However, draft and the allowable radius of swing must be considered when choosing a refuge. Additionally, many of the islands, both large and small, have commercial oyster beds and fishing nets on their northern sides. Destruction of these beds or nets by foreign flag vessels while seeking refuge should be a major consideration of ship captains so as to eliminate, to the greatest degree possible, the straining of relations with local fishermen and authorities.
Kure Harbor is located in the eastern sector of Hiroshima Bay and is literally landlocked by mountainous terrain, some of which exceed 360 meters (1181 feet) in height. To the north and east the mountains are highest, while to the west the maximum height of the islands ranges from 120 to 240 meters (394-787 feet). Islands to the south and southwest reach heights greater than 360 meters (1181 feet). These mountains are a formidable barrier to strong winds and accompanying seas. However, as can be seen from Figure 3, the ridge lines north of Kure are aligned along a northeast-southwest axis so that one could expect the Harbor to experience its strongest winds from the northeast (tropical cyclone passage to the east). Area "F" in the Outer Harbor (Figure 1 and Figure 3), is the "typhoon anchorage" noted by Kure Harbor authorities which is used by a large number of merchant vessels. Area "F" is extremely well protected from westerly winds and would appear to be most open to northerly winds. The mud bottom, ranging from 18-22 meters (60-72 feet) in depth, is characterized by good holding. Smaller vessels usually utilize the shelter of the various coves found around the periphery of the harbor area or remain at pierside. JMSDF deep-draft ships normally go to Area "E" because of the overcrowded conditions in Area "F" and the Inner Harbor. JMSDF submarines normally remain tied up at the submarine pier.
Source: http://www.nrlmry.navy.mil/port_studies/thh-nc/japan/iwakuni_kure/text/topography.htm
