A cloud, dark and ominous, was rolling off the mountain, over Wat Phu, when we arrived there by tuk-tuk from Champasak eight kilometres away.
The leaves shed water from the earlier storms and the lakes were silent black pools of molten metal.
And a brooding quiet engulfed the area: the remains of ancient civilisations seemed to offer some tense communication, a feeling of excitement and the potential for anything, as we walked along the processional track in the gathering gloom.
The cloud, a spatter of warm rain in a soup of thick wet air, hit us as we reached the two giant ruins (picture above) and we sheltered under the sparse cover of two trees with a Lao family.
The black of the ruins glistened in the rain and the deserted greens of new life grew deeper in a silent world.
Wat Phu, which means Mountain Temple, dates back at least a 1,400 years but religious worship on the site is thought to have started much earlier with animists finding sacredness in the mountainŐs spirits and its rock shelter pool.
Later, the Chams more noted for their sites in Vietnam like My Son are thought to have taken the 4,500ft mountain as holy during the 4th century because it is crowned with a rock outcrop shaped like a Shiva phallus.
But its heyday came around 1,000 years ago as a religious and intellectual centre built by the Khmers, part of their network radiating from the centre of their empire at Angkor Wat at Siem Reap in Cambodia and stretching into what is today northern Thailand.
The site has three levels, symbolically going from the lower level, to the middle level, to the mountain. Each level has its buildings, its sacred meanings rippling down the centuries.
Today, it lies largely unrestored offering an experience of walking through the ruins and lingering to see the structures and carvings although work is underway with international money and expertise which has already rescued some of the statues and other art as well as improving the site.
On the lowest level, with the rice paddies stretching away to the horizon, there is a wreck of a palace in front of a huge lake where rituals and festivals were celebrated.
From there, you can walk along the processional path, between two more lakes, with ancient phallic pillars and some statues.
Then, just a little higher, is the middle level where there are two enormous, square buildings: just ruins now, solid walls but little else, where once gender-segregated worship had the areas alive with activity.
There are the remains, too, of a pavilion a stark, imposing building with its age blackened stone gripped by the verdant growth of the centuries.
From there, the path leads up gently, straight, paved, until you reach a large Khmer statue and other remains. Here, pilgrims yes, that includes you can leave offerings of flowers and incense, which can be bought nearby.
The path ends and the stairs begin, steep and narrow like a Mayan pyramid, with places to stop and gaze an the unfolding vista while you sit among the fallen petals of the tree flowers.
But it is at the top of the stairs that the view can take your breath away not the distant plains, as wonderful as that sight is, but the temple itself.
Our climb from the lowest level after the cloud rolled by was hot and the light was poor, with moisture in the air. Then, as our heads rose above the top steps, the sun broke through a monsoon blessing and streamed down through the broken roof of the temple.
Through the door, the Buddha images were alight with spirit and colour and outside the play of light and shadow held us with its beauty. Between us and the door were two small offerings towers of flowers made from banana leaves and docorated with petals glowing in the sunlight.
All around, the ground glistened with the wetness of the season while inside the temple glowed with the light of a thousand years of hope and worship.
We stepped forward, through the pink-grey stone of the door arch, into the temple where the biggest Buddha image was alight in its bright paint, and the others flanked it. In front were the offerings: incense, flowers, candles.
Outside, the solemn, soft beauty of the building offered its wall carvings for us to see, to marvel at: the old Cham art of carving the brick in situ has survived the time, with the white moss creeping over much of it: a captivating living death merging the art of people with the art of nature.
Nearby, a Buddha image (above right) was seated under an umbrella, dignified, a bright slash of orange/yellow in the greens and greys and pinks of the highest level of Wat Phu.
Looking out from the Buddha, the fields and water stretched as far as the eye could see and, more immediately below, the first levels of the complex were laid out like a plan. The buildings for gender-segregated worship were square, stark rectangles of the walls: inside them, nothing. And beyond them, distance repaired much of the damage to the palace as it stood, imposing once again, between the inner lakes and the biggest lake on the other side of it.
In the cool warmth of the sun and the height and the air from higher on the mountain, two women were sitting. They were using the temple wall as the world's most beautiful work area but their eyes were not on the scene below, or the temple itself, but on the offerings they were making.
Their careful fingers(picture right) folded and pinned the banana leaves into cones and then decorated them with flowers and petals.
Worship, after perhaps 2,000 years, was alive and real in the mountain temple.