Sixaola in the context of Río Sixaola

The border between Costa Rica and Panama is 348 km (216 mi) long. The border in its present state is demarcated by the Echandi-Fernandez Treaty of 1941.

The border between the two countries runs between the Pacific and Caribbean coasts, through the Cordillera Central. The Echandi-Fernandez Treaty defined the current border as follows:

Bocas del Toro (Spanish pronunciation: [ˈbokas ðel ˈtoɾo]; meaning "Mouths of the Bull") is a province of Panama. Its area is 4,643.9 square kilometers, comprising the mainland and nine main islands. The province consists of the Bocas del Toro Archipelago, Bahía Almirante (Almirante Bay), Chiriquí Lagoon, and adjacent mainland. The capital is the city of Bocas del Toro (or Bocas Town) on Isla Colón (Colón Island). Other major cities or towns include Almirante and Changuinola. The province has a population of 159,228 as of 2023.

Christopher Columbus and his crew first visited the area in 1502. Bocas del Toro borders the Caribbean Sea to the north, Limón Province of Costa Rica and the Naso Tjër Di Comarca to the west, Chiriquí Province to the south, and Ngöbe-Buglé Comarca to the east. The Río Sixaola forms part of the border with Costa Rica. A newly constructed bridge spans the river between Guabito and Sixaola, Costa Rica. The bridge is a border crossing used by tourists going between destinations in Bocas del Toro and Costa Rica.

The Sixaola River (Spanish: Río Sixaola) is a river in southern Limón Province, Costa Rica. It flows from the Cordillera Talamanca to the Caribbean Sea northeast of Sixaola at 9°34′20″N 82°33′54″W / 9.57222°N 82.56500°W / 9.57222; -82.56500. The river's headwaters are part of the La Amistad International Park. For part of its length, the river forms the border between Limón Province, Costa Rica and Bocas del Toro Province, Panama.

An old railroad bridge that collapsed in 2017 spanned the river between Guabito, Panama, and Sixaola, Costa Rica. This bridge was a border crossing between Costa Rica and Panama and used by pedestrians when traveling between Costa Rica and Bocas del Toro. This bridge has now been dismantled.

Guabito is a corregimiento and town in the Changuinola District of the Bocas del Toro Province of Panama. It is a small town located directly across the Rio Sixaola from Sixaola, Costa Rica. An elevated former railroad grade and bridge connects Guabito to Sixaola. This border crossing is popular with tourists going between Costa Rica and Bocas del Toro, though few tourists stop in Guabito longer than necessary to clear Panamanian customs.

Guabito has a land area of 168.8 square kilometres (65.2 sq mi) and had a population of 8,387 as of 2010, giving it a population density of 49.7 inhabitants per square kilometre (129/sq mi). Its population as of 1990 was 11,125; its population as of 2000 was 14,366.