No. Mexico is located within the mainland of the North American continent, and it has two major peninsulas: the Yucatan Peninsula touching the Gulf of Mexico and Caribbean Sea, and the Baja California Peninsula, touching both the Pacific Ocean and the Sea of Cortes.
Southeastern Mexico...
It is a city located on the Baja California Peninsula, on the country of Mexico.
the south east tip of Mexico beside the Caribbean
the south east tip of mexico beside the Caribbean
Both Belize and Guatemala qualify as such.
It is a peninsula, located in Mexico.
Belize (capital: Belmopan) is the country located on the Yucatan Peninsula, bordered by both Mexico and Guatemala.
Cancun is located on the eastern Yucatan Peninsula, a triangular-shaped flatland mostly composed of limestone. It is located on eastern Mexico.
The Yucatan Peninsula is part of the country if Mexico.
Cancun is located in the country of Mexico. It is located on the eastern side of the Yucatan peninsula facing the Caribbean Sea. It is located in the state of Quintana Roo.
Cancun, Mexico is located in the country of Mexico, along the northeastern coast of the Yucatan Peninsula. It is located along the Caribbean Sea. It is a very popular tourist destination.
On which peninsula?