of hardwood. Many Sandakan wood logs are now found in Beijing's Temple of Heaven. Sandakan also enjoyed modern developments such as telegraph service to London and paved streets before Hong Kong and Singapore. The overseas Chinese have contributed to the development of the town since their immigration in the late 19th century. The immigrants to Sandakan were farmers and labourers while some of them worked as businessmen and entrepreneurs. In the modern days, Sandakan have been poised to become one of Sabah business hubs. The town itself is one of Sabah's major port, other than in Kota Kinabalu, Sepanggar Bay, Tawau, Lahad Datu, Kudat, Semporna and Kunak. Sandakan district is known for its eco-tourism centres, such as the orangutan rehabilitation station in Sepilok Rehabilitation Centre, the Turtle Islands Park, the Kinabatangan River and the Gomantong Caves which are famous for their edible bird's nest. Due to Sandakan geographical proximity to Southern Philippines, there is also a barter trade connection and Sandakan is considered as a transit point for food entering the Southern Philippines. The state government has been assisting traders to improve their trading system and providing infrastructure facilities. Sandakan main industrial zones are basically based on three areas such as the Kamunting area known for its oil depots, edible oil refinery and glue factories. In Batu Sapi, a shipyard, fertiliser oxygen gas and wood-based factories are situated. Since 2012, the State Public Works Department (PWD) has undertaking three projects to upgrade roads in Sandakan. A grand specialised industrial park, Majulah Industrial Centre have also started operating in 2015. The proposed Seguntor industrial area consists of 1,950 hectares (4,833 acres) is originally an agricultural area and the area is now in the process to be re-zoning into an industrial area. 2,531 acres will be for wood-based industries while another 2,302 will be used for general industries. At present, 55 wood-based factories have been approved, of which 35 has been into operation. While another total of 340 hectares area for general industries and 30 hectares for service industries are located in various parts of Sandakan. But in recent years, many businessmen have shifted their operations away from the town centre to other suburbs due to a large presence of illegal immigrants from Mindanao islands in the Philippines which has caused trouble, mostly crime such as theft and vandalism on public facility and also solid waste pollution in marine and coastal areas.