The Casa del Adivino, Uxmal.
It's midday, but the gloom and the dank smell of rotting leaves are unnerving. The path cuts through tangled ferns and undergrowth and, high above, the canopy buzzes with insects.
Completing the scene are grey, lichen-covered remains rising ghost-like out of the forest. The feeling of being watched, of treading on secrets lost, is hard to shake, because this is Sayil, Mexico, one of the major centres of the Maya civilisation.
The Maya built cities across Mexico's Yucatan Peninsula and in what are now the countries of Belize, Guatemala and Honduras. But it was those who lived in the northern and central areas, including the Yucatan, who excelled in mathematics, astronomy and astrology. Their culture has cast a long shadow, with many believing the Maya Long Count calendar contains an ancient prediction that the world will end this Friday.
War, drought and overpopulation are thought to have caused the disappearance of the Maya civilisation by the early 10th century. While Maya still live in Central America, the peak of their civilisation as recorded in Sayil and its neighbouring ancient ruins is a distant memory.
Their tragic story, however, has left an intriguing string of ruins to be explored by those weary of the crowded beaches of Cancun and Playa del Carmen. Many of the most impressive sites can be seen on a three-day road trip from Cancun, with time left over to relax in the crumbling grandeur of haciendas and dive into the cool subterranean waters of the region's cenotes.
The beautifully restored colonial city of Campeche is an easy half-day drive from Cancun along the Ruta Puuc, a jungle road that wends its way through a series of Maya cities: Sayil, Xlapak and Labna. While not the largest, nor best restored, cities in Mexico, the Ruta Puuc sites offer some remarkable stone carvings and give a sense of how the cities appeared to the archaeologists who discovered them a century ago.
The road is narrow, with jungle vegetation creating a green tunnel that changes little from one kilometre to the next, breaking only to reveal an entrance to Sayil.
The Puuc Maya civilisation flourished between AD750 and 950, and is named after the region's hills. They are low and subtle, and the regular undulation of the land is hypnotic, inducing a suitable mindset for a first glimpse of Sayil's El Palacio, a three-tiered building with an 85-metre-wide facade. The distinctive columns of Puuc architecture remain straight and tall, supporting stylised Chac masks and the figures of other Maya gods carved into the rock. But not all the grotesque creatures here are carved of stone. The ruins are home to large lizards that occasionally interrupt their sunbathing to scurry across the ancient stonework.
Labna is the one city on the route that should not be missed, with its enormous palace displaying some of the best-preserved carving in the region. Archaeologists believe there were 3,000 people living here in the ninth century, but today I'm kept company only by serpents' heads sporting the faces of people, which compete for space with human figures and walls covered in decorative patterns.
From here it's a short drive to Santa Elena, a small town with a good range of guesthouses, through Kabah, which was one of the most important cities in the region. Remains here include the facade of El Palacio de los Mascarones, covered in nearly 300 carved masks, and El Arco, which once marked the start of a key road leading to Uxmal, the most impressive city in the region. The jungle road has disappeared, but standing in the grand archway in the glow of the afternoon sun gives me my bearings for tomorrow.
Uxmal is much larger than the cities of the Ruta Puuc, and better preserved, with some structures having been extensively restored - again. The city was rebuilt five times between the first settlement, in AD600, and its abandonment, in AD900.
No one is quite sure why Uxmal was abandoned, but archaeologists think drought played a role. Chac, the rain god or sky serpent, is depicted on build-ing facades with a great deal of regularity, indicating the importance of rain to the Maya here and elsewhere. Another clue is offered by the many cisterns that Uxmal's inhabitants created to store water during the long dry spells.
Among Uxmal's grandest sites is the Casa del Adivino, the 39 metre-high temple that greets you as you enter the city. The 74-room Nun's Quadrangle is thought to have once been a military academy or royal school. The walls of the four temples that surround the green lawn of the quadrangle are carved with serpents and phallic images.
The Maya's was one of the most intellectually advanced cultures of pre-Hispanic America, although much of it was centred on serving rich leaders. Few records mention matters concerning the working classes. Maya cities were all built without the use of the wheel or heavy draught animals such as oxen and horses, creating centuries of backbreaking work for the common man.
Unlike me, they probably couldn't turn their backs on these cities on a whim, to go for a swim, for example. The Maya, and the Spanish landowners after them, relied on cenotes, or sinkholes that connect to subterranean water bodies, for supplies during dry periods. The entire Yucatan peninsula is dotted with them.
Cenotes de Cuzama is a series of three sinkholes near the village of Chunkanan, just east of Merida. They're located on an old plantation and connected by a narrow-gauge rail line, along which horses pull cars.
Parched and overheated, I stop beside the first cenote. I clamber down the wooden ladder that pokes from a hole in the ground measuring only a metre across. The cave opens into a wide, echoing cavern, dark save for the few rays that fall through the opening in the ceiling. Floating in the cool, clear water, looking up at stalactites that glow a dull yellow in the darkness, each drip that echoes through the cenote is a bittersweet reminder of the fate that befell the Maya.
Getting there: Cathay Pacific www.cathaypacific.com  flies from Hong Kong to Los Angeles, from where Aeromexico aeromexico.com  operates a service to Campeche, Mexico, with a stopover in Mexico City.