Neighbouring South American countries Suriname and Guyana share what apart from a border?

Question

Because of its major oil deposits, which South American country was a founding member in 1960 of the Organization of the Petroleum Exporting Countries (OPEC), the only South American country in OPEC at that time?

Answer 1

Vehicles in both drive on the left
They are the only two countries in South America to drive on the left. Although Suriname is the smallest sovereign state in South America Guyana is only the third - the second smallest is Uruguay.