Gulf of Mexico: Two Nations, One Peninsula

The Gulf of Mexico is bordered by:

• United States (Texas, Louisiana, Mississippi, Alabama, Florida)
• Mexico (Tamaulipas, Veracruz, Tabasco, Campeche, Yucatán)
• Cuba (north coast) — often overlooked but shares maritime boundary.

The peninsula in southeastern Mexico is the Yucatán Peninsula—separating the Gulf from the Caribbean Sea. It comprises the Mexican states of Yucatán, Quintana Roo, and Campeche, plus Belize and Guatemala’s Petén region.

Key features: Cancún, Mérida, Chichén Itzá, Tulum, Sian Ka’an Biosphere. Geologically, it’s a limestone platform—cenotes, underground rivers, no surface rivers.