The air was thick with the familiar scent of yak butter and incense. Monks, bleary-eyed and squinting under the sun, filed out of the temple at Drepung Monastery. Across the courtyard, a middle-aged initiate in an ochre robe spoke on a mobile phone. Morning prayers complete, it was time to check in with the world below, the one changing as rapidly as the sky above.

Few places have witnessed as many transformations as Tibet. Throughout its long history, it has endured invasions from the likes of Genghis Khan, and more recently Mao's Red Guards. These days something less violent, but still threatening, is overtaking the culture: tourism.

Twenty minutes away in Tibet's capital, Lhasa, a local Tibetan guide named Dorje (not his real name) reflects on the recent changes. He has high blood pressure and a ruddy complexion caused by living at almost 4,000 metres above sea level. He looks far older than his 40 years.

"I was quite sick last year–food poisoning–and had to take time off work," he says. "I bought a plastic bag of small fish and released them into the river at New Year's. We Tibetans believe the more lives we save the more blessings we can receive."

We're sitting inside Yubouzu, a Chinese fast-food restaurant set amid a tangle of karaoke bars and mobile-telephone shops about two kilometres from the iconic Potala Palace. Since the July 2006 opening of the Qinghai–Tibet railway, the first railroad linking Tibet to the rest of China, approximately 4,000 tourists have been pouring into the city each day. Flights into Gongga Airport have also increased.

Although the influx of Chinese tourists means more money for the impoverished region, it hasn't had much of a positive effect for Dorje and other guides who don't speak Putong ­hua. In fact, they have come under increased suspicion from authorities, who question their allegiance to Beijing.

He goes on to explain how he tries to stretch the meagre 150 Chinese yuan ($22) that he earns each day during the tourist season to support his wife and 10-year-old daughter. Dorje's work begins in March and runs until November.

A cursory glance around the capital reveals how the Chinese influence has affected local culture in ways that are unsettling, even to foreign observers. A steel telecom tower now sits on top of the once-holy hill of Chagporo, adjacent to the Potala Palace. Come nightfall, it is illuminated into a garish neon-red Eiffel Tower look-alike.

The local Tibetan population has been squeezed into a small area around the Jokhang Temple, while the steady influx of Chinese continues to expand the city's boundaries, shooting up prices for real estate and other commodities.

Dorje acknowledges the benefits and improvements that the government has made, mainly in Lhasa–the renovations to temples, the schools, and the availability of goods–but he can't conceal his anxiety about the future.

"Everything is more expensive. Sixty percent of Tibetans are unemployed and the price of land is going up. I worry about my daughter's future."

No trip to Tibet is complete without a tour of the Potala Palace. Built on Mount Mapori, construction on the palace by Lobsang Gyatso, the great fifth Dalai Lama, began in 1645. But as we are planning our visit, authorities inform us that we will only have one hour to take it all in.

After registering at the gate we start our ascent on foot. Lhasa spreads out before us as the palace's white walls rise to our right.

Once inside, we soak up as much of its history and grandeur as possible; we view the Dalai Lama's quarters and the huge stupa dedicated to the fifth Dalai Lama. Old crumpled bills left by pilgrims poke out from cracks or are stuffed into the wire mesh surrounding the golden statues. It all seems very lonely and without purpose with the leader in exile.

The next day, we travel an hour outside Lhasa to the Ganden Monastery. Ganden, meaning "joyful paradise", was once a huge university that was home to 3,300 monks. It was desecrated and razed before and during the Cultural Revolution. It was nothing more than a blackened shell until the early 1990s when the Chinese authorities allowed restoration work to begin.

Today, much of it has been rebuilt. Rather than apologize for past atrocities, it seems the Chinese authorities have allowed such projects to go ahead to make up for the damage once inflicted.

We turn off the main road heading into the valley and begin the long, winding ascent over a gravel road currently being paved. Ganden straddles a small mountain overlooking a sprawling valley. Dating from 1409, it has been a centre for the "yellow hat" Buddhist sect and its founder, Tsongkapa. Thus, it is of significance to the current Dalai Lama, who originates from the same sect.

Recently, tension has been brewing between the Dalai Lama and a small group of monks at Ganden. The Dalai Lama issued a decree last year banning the worship of a controversial figure here, and some monks refused to accept it. Small clashes have broken out.

Dorje discouraged us from visiting but eventually agreed to come after he said some prayers to protect himself from any bad karma.

Once at the top, we begin walking the kora with stunning views of the surrounding hills and valleys. A kora is a core ritual for Tibetans that involves a clockwise circumambulation around a holy site or sacred object. Believed to bestow blessings on those who complete it, most monasteries have one. It includes prayer wheels and colourful flags known as "wind horses", which most Tibetans believe deliver prayers across the sky to the gods.

Ganden is one of the few sites to hold sky burials, a Tibetan ritual for disposing of the dead. Tibetan Buddhists believe the material body represents nothing at death and that all meaning resides in the soul. A sky burial entails cutting the body into pieces and burning the bones.

No ceremonies are planned for the day we visit, but a large flat stone and tools stained with blood suggest that one has taken place within the last day or two. As we gather at the site, vultures circle overhead.

On our return to Lhasa, Dorje explains that he believes the Chinese influence is here to stay. But as with much Dorje says, it is difficult to gauge his true feelings. He is wary of everyone. After all, the tourists come and go, and it is the Tibetans who are left behind. Either way, his family is adjusting: his daughter is studying hard to learn Chinese.

ACCESS: China Eastern Airlines flies from Shanghai to Lhasa via Xian. Tibet Travel Expert ( www.Tibet-Tour.com/ ), based in Shanghai, offers tours and arranges all necessary travel permits.