Bordering Guatemala on the southeast and the Pacific Ocean on the southwest, Chiapas is Mexico's southernmost state. This naturally scenic region features mountainous highlands and lowland tropical rainforest dotted with lovely Spanish colonial towns, pristine beaches, breathtaking waterfalls, magnificent aquamarine lakes, an active volcano, and a predominantly Mayan indigenous population. Chiapas' impressive Mayan archaeological sites are arguably the main attraction. These include, among others, the ancient Palenque ruins, which feature remarkable carvings and hieroglyphs and a serene forest setting, the smaller but no less dramatic twin sites of Yaxchilán and Bonampak, and Toniná with its steeply pitched main pyramid and macabre murals and statues. Other popular attractions include the spectacular waterfall park of Agua Azul and the colonial city of San Cristóbal de las Casas, which boasts a beautiful old town and a lively market centre.