As one walks along the pedestrian-only roadways, it is music and birdsong that filter through the banyan trees, not traffic noise or pile-drivers. Ivy-covered wrought-iron gates open on to vast colonial-style shuttered mansions. Around one corner, a pretty white church sits in landscaped gardens. The air is clean, and not one smokestack chimney can be seen. Can this really be China?
Gulangyu offers that rarest of commodities on the Chinese mainland - peace and quiet. The British had an eye for the island's potential as a comfortable repose when in 1842, after the first Opium War, they forced China to open Xiamen on the south-east coast as one of the foreign treaty ports. Across the harbour sat verdant Gulangyu, and that was where the interlopers were enticed by the scenery to set up home. A dozen foreign consulates were soon established, and with them came the missionaries - and lots of pianos.
"We have many pianos from Britain, because the climate here is damp so British pianos are better," said 59-year-old Yin Chengdian, who runs the island's music school. And the one-square mile "Piano Island", as it is called by the 20,000 inhabitants, is determined to live up to its reputation. There is the ferry building, which is shaped like a piano; and the island's concert hall, shaped, you guessed it, like a piano.
The history of the piano on Gulangyu is the history of the island itself. "In the second half of the 19th century the Western missionaries came here and brought the music," said Mr Yin. A tradition was quickly established. "The wives of the missionaries were very good music teachers. So they taught the local Chinese." As Gulangyu developed as a Western enclave, scores of wealthy overseas Chinese also started to drift back, and built themselves stately European-style mansions, faced with exquisite art deco stonework and stucco decoration. And with them came more pianos.
Even when the Japanese invaders came in 1938, the music played on. Then in 1949, in the wake of the Chinese Communist victory, the Westerners and rich overseas Chinese departed. "But all the pianos were left behind," said Mr Yin.
During the first years of the new order, piano playing was politically acceptable, and by 1959, Mr Yin's brother, Yin Chengzong, had emerged as one of China's most promising pianists, one of a number of star musicians to hail from Gulangyu.
In 1966, with the outbreak of the Cultural Revolution, the music stopped. A history of pianos and priests brought the inhabitants of Gulangyu no sympathy from the crazed Red Guards. Zhang Zhenzhen, the 46-year-old curator at the museum, said: "In some households I heard the pianos were smashed. The Red Guards came to our house and took away a lot of music books." Mr Yin added: "People just did not play the piano. Because Western classical music was considered like capitalism."
The Christian Yin family, like many others, were thrown out of their home. Mr Yin's famous pianist brother decided collaboration was the best chance of survival and became a favourite composer of revolutionary ballads - such as "A new song from the countryside" - for the Gang of Four.
At the end of 1976, after the death of Mao Tsetung, the music re-started just as suddenly as it had halted. Mr Yin was the piano accompanist at the first public concert. "The young singers gave a better performance than the older ones who were shaking so much they could not sing very well," he remembered. His by now infamous brother left for America as soon as he could. Plans for a music school started in the early 1980s, and it opened in 1990 on top of a hill in a converted Thirties American missionary church. There are 180 full-time students.
Across Gulangyu, some old homes, including the Yins', have been returned to their original owners. Others have been renovated as holiday homes for powerful state work units. Drawn by the seafood as much as the music, China's leaders often find the time for an inspection tour of Gulangyu. One photograph shows the prime minister, Li Peng, triumphantly holding a lobster at the Huang Yan Dong restaurant in 1995.
Deng Xiaoping came in 1984, and Richard Nixon also made it to the island. Like all VIPs they stayed at the Gulangyu Hotel, built in 1923 as a private house by the the Huangs, an overseas Chinese family from Indonesia.
The Huang descendants are not in residence. A hotel manager reluctantly explained: "The property belongs to the Huang family, but the government runs the hotel and pays rent to the Huang family," she said. How much rent? "Well, in the past, the government did not pay any rent." So how much do they pay now? "Well, they don't actually pay rent now." So how does the Huang family feel about this? "Maybe the Huang family wants it back, but we don't know how to solve this problem."