<P> The main river in the parish is the Black River, and measuring 53.4 kilometres (33.2 mi), it is one of the longest rivers in Jamaica . It is navigable for about 40 kilometres (25 mi), and is supported by many tributaries including Y.S., Broad, Grass and Horse Savannah . The river has its source in the mountains of Manchester where it rises and flows west as the border between Manchester and Trelawny then goes underground . It reappears briefly in several surrounding towns, but reemerges near Balaclava and tumbles down gorges to the plain known as the Savannah, through the Great Morass and to the sea at Black River, the capital of the parish . </P> <P> The geology of the parish is primarily alluvial plains to the south, and karstic limestone to the north . The karstic zones are known to contain over 130 caves (Jamaica Cave Register as of 2007 - from Fincham and JCO). These include Mexico Cave and Wallingford River Cave, near Balaclava, which are two associated sections of a major underground river that has its source in south Trelawny, as well as Yardley Chase Caves near the foot of Lovers' Leap, and Peru Cave, near Goshen, which has stalactites and stalagmites . Mineral deposits include bauxite, antimony, white limestone, clay, peat and silica sand which is used to manufacture glass . </P> <P> The parish had an estimated population of 148,000 in 2001, 4000 of whom live in the capital town . The distinct feature of this parish is that numerous ethnic groups can be found here; St Elizabeth probably has the greatest ethnic mixture in Jamaica . St. Elizabeth provides the best testimony of the Jamaican motto--"Out of many, one people". The Meskito (corrupted to' Mosquito') Indians brought to Jamaica to help capture the Maroons, were allowed to settle in southern St. Elizabeth in return for their assistance and given land grants in this parish . This parish has also attracted Dutch, Spanish, Indian, Maroon, mulatto, English, and European inhabitants from the 17th century onwards, with the result that many observers feel that it has more people of mixed - race ancestry than can be found in any other part of the island . </P> <P> In the 19th century Irish, Spanish, Portuguese, Scottish, Germans, Chinese, and East Indians migrated to Saint Elizabeth . There are pockets of ethnic concentrations in the parish, including Mulatto and Creole, notably found in the southeast . </P>

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