Hong Kong was a British colony between 1847 and 1997
By Michael Bristow
BBC News, Hong Kong
The world has many great journeys, trips which are more than just travel between two points - they reveal something about the land.
There are epic car drives, train rides across continents and walks that retrace the steps of pilgrims.
But rarely do these journeys extend for just a few hundred metres.
The Lo Wu border crossing that separates Shenzhen, in mainland China, from Hong Kong is an exception.
If it were not for the passport and security checks, the whole trip would take just a few minutes to complete on foot.
Hong Kong is different and that is the result of its unique history
It is not even a scenic journey.
The checkpoints on either side of the divide are housed in ugly, squat concrete buildings.
The walk between them is across a covered bridge which spans a murky river.
But this is still a great journey because of what it reveals about the two sides.
As many as 300,000 people pass through this border every day.
Betty Hong works on the Hong Kong side. She oversees this human tide.
In Shenzhen, the newspapers on sale mostly repeat the propaganda dictated by officials in Beijing
For some, the job would be dull and monotonous but not for her.
She told me that she prides herself on making sure nearly everyone gets through in less than 30 minutes.
In some respects, Lo Wu looks like many other checkpoints across the world. There is the trade in goods, for one.
On the mainland side, young men dart to and fro on bicycles fitted with a square piece of plywood on the back.
Goods are piled high on these small platforms - products that have just been brought over the boundary line or are destined for Hong Kong.
And on both sides of this crossing point there are shops selling last-minute gifts and souvenirs.
But it does not take a keen eye to notice that there is also something very different about the two sides of this border, something that shows they are governed not just by different rules, but also by different ideas.
In Shenzhen, the newspapers on sale mostly repeat the propaganda dictated by officials in Beijing.
But just a short distance to the south, in Hong Kong, a reader can get access to a far greater wealth of news, information that is free from government censorship.
Newspapers like the UK's Financial Times are readily available.
It is also immediately clear that Hong Kong is more connected to the outside world.
On that side of the border, there is a branch of the convenience store 7-Eleven.
And weary travellers can pause for a cup of coffee at Starbucks.
The language is different too.
Border guards in Shenzhen speak Mandarin, a northern language that is used by Beijing as a tool to unify China's vast territory.
But in Hong Kong, officials still speak the local Chinese dialect, Cantonese - an expression of their own, separate identity.
These may be fragmented images but they suggest Hong Kong is out of step with the rest of China.
And that is true. Hong Kong is different and that is the result of its unique history.
Until it was handed back to China in 1997, it was a British colony, ruled by a governor despatched from London.
Many Chinese cross to Hong Kong every day for work
A mix of Chinese hard work and British order allowed the colony to grow rich and successful.
That formula was preserved after the handover, using the principle of "one country, two systems".
China got rid of the British but Hong Kong got to keep its own rules.
That is why it is still more open, more international and freer than the mainland.
A visitor returning to Hong Kong today after a 20-year absence would not really notice many differences.
Of course some things have changed in the decade or so since the handover.
There are now more mainlanders crossing the border.
I met two of them in one of the crowded restaurants on the Shenzhen side. These two women had just come back from a five-day shopping trip in Hong Kong.
I shared their table as they happily bolted down a meal of roast duck on rice, before dashing off to catch a plane.
One of them was clutching a new Louis Vuitton bag.
"We just love Hong Kong," said the one with the designer accessory.
The break, she said, had given the two childhood friends valuable shopping time together before they headed back to their government desk jobs.
But it is the lack of change which I think is more interesting.
When I first visited Hong Kong two decades ago, I did not think much about the differences.
After all, Hong Kong was still British. It was handed back to China just as the country's opening up to the outside world was gathering pace.
Many thought - or hoped - that China would become more like Hong Kong, with its freedoms, its tolerance and its rule of law.
But the rights of mainland Chinese are in many respects as restricted today as they have ever been.
So Hong Kong and Shenzhen still offer two sharply contrasting views of how to organise society.
And a short walk across the Lo Wu border point makes all that abundantly clear.
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