Uruguay's only land border is with Rio Grande do Sul, Brazil, to the north. To the west lies the Uruguay River, to the southwest lies the estuary of Río de la Plata, with Argentina only a short commute across the banks of either of these bodies of water, while to the southeast lies the southern part of the Atlantic Ocean. Uruguay, with an area of approximately 176,000 km2, is the second smallest nation of South America in area after Suriname.