The peninsula has a spine and Borneo does not, and almost every routing mistake comes from ignoring that. On the west coast, the electric ETS trains run from Kuala Lumpur north through Ipoh to Butterworth, opposite Penang: about two and a half hours to Ipoh for €5 to €9, and four to five hours to Butterworth for €12 to €16. Seats are sold online and Friday and Sunday services fill, so book a few days ahead. It is the most comfortable travel in the country and the reason a first trip usually stays on this side.
Coaches cover everything the train misses. From the TBS terminal south of Kuala Lumpur you can reach Melaka in two hours for €3 to €5, the Cameron Highlands in about four for €7 to €10, and the east coast in five to seven. The vehicles are better than the price suggests, and the terminal is on the rail network, so getting to it is not a taxi problem.
Within cities, use rail and Grab together. Kuala Lumpur's MRT, LRT and monorail cost under €1 a ride and reach most of what a visitor wants; George Town, Melaka and Kuching are walkable in their old cores, with Grab at €2 to €5 for anything beyond them. In Langkawi and the Cameron Highlands a rented car or scooter, €7 to €20 a day, costs less than two taxi crossings and gives you the day back.
Borneo is a flight, not a detour. Kuala Lumpur to Kota Kinabalu is about two and a half hours, and to Kuching under two; fares are cheap booked ahead and expensive booked late. Once in Sabah, the road from Sandakan to the Kinabatangan lodges is two to two and a half hours, and it is usually arranged as part of the lodge package. The east-coast island ferries, to Redang, the Perhentians and Tioman, reduce or stop from roughly November to March, so check the season before you commit to a room.
The one habit worth building is slack around separate tickets. A peninsula-to-Borneo flight, an island ferry and a wildlife transfer are three contracts, not one journey, and nobody protects the connection between them. Leave a night, or at least half a day, between the legs that would ruin the trip if they slipped.
Sources
- Malaysia travel guide, Tourism Malaysia, accessed
- KTMB intercity and ETS train services, Keretapi Tanah Melayu Berhad, accessed
- Kinabatangan River and Sepilok visitor information, Sabah Tourism Board, accessed