A Swiss customs officer and her dog searching a suspicious car at the border between France and Switzerland, near Geneva Photo: Pierre Albouy
On many quiet country roads, there are often no customs posts at all, and travellers coming from neighbouring EU countries do not have their passports checked.
I was able to walk into Switzerland from France down a quiet country road next to a wheat field at the village of Landecy, near Geneva, without a care in the world, and I was almost tempted to break into a yodel.
There was an old border hut next to the road, but when I looked in the window it was empty and unmanned.
A local man told me the hut had not been used for 20 years.
Vehicles at the border crossing Photo: Pierre Albouy
Although I was entering a country that is not in the EU, there was nobody there to check my passport - or root through my bag for contraband drugs, weapons and salami (which is commonly smuggled into Switzerland because of the extortionate price of meat).
There are still a small number of customs checks on cars entering the country, but the local officials told me they rely on gathering intelligence.
They collect information and pounce on suspect vehicles to catch smugglers, rather than monitoring every vehicle that moves.
And cars and trucks may be stopped miles away from the border.
We are now approaching the anniversary of Britain voting to leave the EU, but we are still far away from knowing what the shape of our own land border with the North will be.
Will there be border posts, and customs checks on every road across the border?
With the hard Brexiteers in Theresa May's cabinet still insisting that Britain will not be part of any customs union, Switzerland offers a glimpse of what our post-Brexit future could be like.
It may be outside the EU, but Switzerland still has a close trading relationship with the bloc, and has signed free trade agreements with EU countries.
Up to 300,000 workers cross into the country every day for employment.
Swiss shoppers cross the border in the other direction looking for bargains.
This is a country that is sometimes disparaged, most famously with the Orson Welles line in the film 'The Third Man': "In Switzerland, they had brotherly love, they had five hundred years of democracy and peace - and what did that produce? The cuckoo clock."
But other countries are now looking at their innovations when it comes to customs controls. The Irish customs authorities are showing an interest in the "Swiss cheese model" with a view to Brexit.
When I visited the busy Bardonnex crossing from France into Switzerland soon after 8am, it was rush hour.
Thousands of French commuters were travelling over the border to their work in Geneva, but the traffic was flowing freely - much faster in fact than the Long Mile Road into Dublin.
It seemed that hardly any cars were being checked, but appearances can be deceptive.
Customs official Jacqueline De Leon told me: "We rely on risk analysis. It doesn't make sense to have patrols everywhere, so we rely on highly selective checks."
When I was at the Bardonnex crossing point into Switzerland, the border patrol pulled over a navy blue Mercedes with an Albanian registration plate.
According to the risk analysis of the Swiss customs authorities, a high proportion of Albanian-reg Mercedes cars are stolen.
So, the officers checked the car from top to bottom, and the inspection took up to four hours.
A sniffer dog jumped into the boot, and electronic scanners looked for traces of drugs. There were suspicions that this car had Albanian mafia connections.
The free flow of cars into a country that is not in a customs union with the EU will be heartening to the thousands of Irish motorists who cross the Irish Border every day.
Does it indicate that life will not necessarily be unbearable for those commuters after Brexit?
Laurence Coudiere of the Organisation of Crossborder workers said: "There is free movement of employees across the border, and if you are from an EU state you can get a work permit easily."
Those crossing the border can bring in goods worth up to 300 Swiss Francs (€275) every day without taxes, and there are limits on imports of meat, dairy products, alcohol and cigarettes.
While motorists are largely unimpeded, the situation for truck drivers is a lot more difficult. When I visited the main border crossing from France near Geneva, there was a queue of lorries up to 300 metres long. Each one had to submit its customs papers.
As with the motorists, the lorries are assessed according to risk, and the suspect vehicles are electronically scanned.
Jacqueline De Leon says: "We know a lot of the trucks that are coming through, and the companies they belong to, and we don't have to check them regularly.
"We look at the risks for certain trucks, and these change all the time.
"At the moment, we have a lot of ham and sausage coming in undeclared from southern Europe.
"And there are a lot of drugs and cigarettes coming in from Eastern Europe at the moment - so we are checking lorries from there more rigorously."
Professor Claudio Bolzman, an expert on migration at the University of Geneva, says one of the main reasons why there is free movement across the border is Switzerland's membership of the Schengen area of European states.
This allows for passport-free travel between 26 countries.
Switzerland is one of only four countries that is inside Schengen but outside the EU.
Prof Bolzman says many of the customs checks in Switzerland now take place far away from the border.
"You can have a French car being stopped 20km inside Switzerland."
The vast daily movement of French workers across the border is not universally popular in Switzerland.
Some political parties have called for greater restrictions.
But Professor Bolzman says a city like Geneva really needs the manpower coming over from France, particularly in areas such as the health service.