That was in the late 1980s - the golden era of Hong Kong's factory canteens and Kwun Tong's industrial area, located at the south end of Kwun Tong Road. Nearly 200,000 workers packed the cluster of factories that churned out everything from garments and plastics to electronics and paper, all for export.

But all that is a distant memory. Many of these industries have moved to the mainland or Southeast Asia to capitalise on lower rents and cheaper labour. Gone are the busy assembly lines, buzzing machines, hard-working employees and chimneys emitting clouds of heavy smoke.

Factory buildings have given way to glass-and-steel office towers, as post-handover administrations envisioned turning Kwun Tong into a new central business district. That scheme took another step forward with The Link Reit's announcement on Wednesday of plans to convert industrial buildings into malls.

The industrial area in Kwun Tong - Chinese for 'government ponds', a reference to the salt pans that once covered the area - didn't exist until the colonial government reclaimed the land in 1954.

The development was spearheaded by both private enterprise and government. An example of the latter is the Housing Authority's now-demolished seven-storey Kwun Tong Factory Estate. Industry is still reflected in the area's auspicious road names - Hung To ('great prospect') and Hoi Yuen ('profit-making').

Most of the factories were small, with fewer than 50 employees, according to a 1972 study by Chinese University.

But those good times are over, and more than half of the 100-odd factory canteens in the area folded. Chong closed 11 of his 13 factory canteens, beginning in the late 1990s. He still owns two, although he said he could 'barely make any money out of them' as rents and other costs soared.

'Times have changed. Factory canteens mirrored the rise and fall of this industrial area,' he said.

Chong said white-collar workers have told him they are embarrassed to eat in his cafeterias, and gravitate instead towards the more expensive restaurants that have sprouted in the area. The Room, for example, is a Western-style restaurant on Hong To Road where meals cost about HK$100 on average. Its spokesman, a Mr Lui, said the restaurant opened 'in the right place at the right time', as offices settled into the area.

'However, the demand in Kwun Tong still doesn't compare to that of Central or other business districts,' Lui said.

'Many restaurants came and went in the past few years.'

The economic transition in Kwun Tong in the early 2000s also turned the former industrial hub into an artists' commune. The first to arrive were filmmakers like Johnnie To Kei-fung and Andrew Lau Wai-keung, who moved their operations to Kwun Tong. Many of To's recent films were shot in and around the area.

And then came the musicians. 'We were attracted by the low rent and large spaces here,' said Kimi Lam, spokesman for Hidden Agenda, a live house for rock and indie music on the second floor of a factory complex on Tai Yip Street.

Another attraction is that bands can play their music as loud as they want, because nobody lives nearby.

Lam estimated that in 2010, about 600 bands occupied factory buildings in Kwun Tong and used them as practice rooms.

But even their days are numbered, Lam fears, as the government's redevelopment plans have sent rents surging.

According to Lam, the rent for their 4,000 sq ft venue was HK$10,000 in 2010. Now it is HK$25,000.

'Lots of bands seem to have disappeared, because they have to share practice rooms now,' Lam said.

While the changes in the industrial zone have been more gradual, those living in Kwun Tong's residential area are facing a more drastic adjustment. Buildings in the once-bustling Yue Man Square will soon be torn down, their thousands of inhabitants making way for a colossal HK$3.9 billion residential and commercial complex on the 570,000 sq ft site. The project began in 2009 and is expected to be completed by 2021.

Yuen Chi-yan, who grew up in Kwun Tong, laments the loss of the community. 'For me, more than just an industrial area, Kwun Tong is a unique place where people of different political backgrounds, ethnicities and classes co-existed.'

Yuen and a team of volunteers have been gathering oral histories in Yue Man Square since 2005 by talking to local residents, street vendors and shop owners, then posting their thoughts and photos on the internet. The website has so far attracted nearly 500,000 visitors.

Yuen's cherished memories of Kwun Tong include watching old films at the Silver Theatre, first opened by a leftist group in 1963, and watching the Chiu Chow community celebrating the Yu Lan Ghost Festival. Both have become impossible since the theatre closed in 2009 and people have moved out of the area.

These are also hard times for the hawkers and small-business owners who have been here for up to 40 years. Leung Kam-hung, the last racing-pigeon vendor in Hong Kong, has been running his stall since 1979. Authorities are now urging him to move to Hong Lok Street in Mong Kok, famous for its bird market.

'But they don't allow me to sell racing pigeons any more. I'm in my forties, and I've been selling pigeons all my life. I don't know what else I can do if I'm not allowed to do that.'

Yuen says the reconstruction project has changed the lives of these hawkers. 'They've been doing business here peacefully their whole lives. Now they need to learn to negotiate with government officials. It's a kind of citizenship education for them.'

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