A variety of ferries and speedboats depart from Penang , on the west coast of Peninsular Malaysia, to Medan and from Melaka , south of Medan, in southern Malaysia, to Dumai . You can also take ferries from Johor Bahru , in far southern Malaysia; from Singapore to the Sumatran islands of Batam and Bintan ; and from Port Klang , near Kuala Lumpur, to Tanjung Balai in Sumatra.

There are two entry points between East Malaysia and Kalimantan . You can catch a bus between the capital of Malaysian Sarawak at Kuching to Kalbar's capital, Pontianak; alternatively, you can cross from the East Malaysian state of Sabah by catching a two-hour ferry to Pulau Nunukan from Tawau, two days' bus ride southeast of Kota Kinabalu.