The geography of the Valdivia area consists of wetlands and alluvial terraces. Several rivers, such as Cau-Cau, Calle-Calle andCruces joins near the city forming the larger Valdivia River. Valdivia River in turn empties to Corral Bay in the Pacific Ocean just some 15 km west of Valdivia. This river network made Valdivia a trade center even since Pre-Hispanic times. The city itself was built on a riverine terrace but expanded later over adjacent wetlands. Nowadays the city is virtually surrounded by hills by all sides except north where Valdivia's lowlands connect to the flatl ands of San Jos� de la Mariquina. The hilly areas around Valdivia are covered with forest, some of which correspond to planted exotic species such as Douglas-fir, Pinus radiata and Eucalyptus globulus. Other areas of forest are used for conservation and recreational purposes although some parts the forest have given place to new urbanizations
