Which peninsula includes Malaysia's western mainland and extends south toward Singapore?

The Malay Peninsula includes Malaysia's western mainland and extends south toward Singapore.

It runs from the Isthmus of Kra in southern Thailand toward the Singapore Strait. The peninsula is bordered by the Andaman Sea and Bay of Bengal on the west and the Gulf of Thailand and South China Sea on the east. Its southern end is separated from Sumatra by the Strait of Malacca.

Several countries occupy the peninsula, including Thailand, Malaysia, Myanmar, and Singapore, with small portions of southern Thailand and Myanmar at its northern end. The Titiwangsa Mountains form a major north-south spine through Peninsular Malaysia. The region has long been important for maritime trade because ships moving between the Indian Ocean and the South China Sea pass through nearby straits. “Peninsular Malaysia” specifically means the Malaysian part of the peninsula, not the entire geographic landform.