The Mekong River forms a border between Thailand and Laos.
what geographic
The Uruguay River forms the western border of Uraguay with Argentina.
chile
Mekong
The river sperating Thailand and Laos is the Mekong River
The Mekong River forms much of the border between Laos and Thailand. It is a major river in Southeast Asia that flows through multiple countries.
The Mekong River forms the border between Laos, Thailand, and Myanmar. Technically, it does not flow through Laos; it does, however, border or touch Laos.
The Mississippi River forms the western border of Illinois.
The Mississippi river forms the western border of the southern colonies.
The Uruguay River forms the western border of Uraguay with Argentina.
Minnesota only forms a border for one country: Canada.