The beefed up border between Bulgaria and Turkey.
Stefan Rousseau PA Archive
In an unequal, globalised world, should we be able to move between states as freely as we can within them?
A disused customs post on the border between Ireland and Northern Ireland.
The border across the island of Ireland is to become the only direct frontier with Europe, which is a major political problem.
Lettuce farmers from Oaxaca working in Mexico City.
AP Photo/Nick Wagner
US elections surfaced fears of Mexicans crossing into the US. But their numbers are actually in decline. Why are they choosing to stay in Mexico? Two migration experts went there to find out.
Could British border controls stretch to Dublin?
Niall Carson PA Wire
Proposals for the UK government to move its border to Irish ports of entry show how many options are now on the table.
An Indian coalmine worker walks along the Stilwell Road after a day’s work in Ledo town, at the Indian-Burmese border.
The Pangsau Pass between Burma and India illustrates the complex issue of borders in the region.
These days neither the public nor governments consider passports as a serious obstacle to freedom of movement.
In the 20th century, governments considered the “total abolition” of passports as an important goal and discussed the issue in several international conferences.
The Brahmaputra is known for its unpredictable fury. Assamese plains dwellers are often victims of floods but also earn a livelihood from the river.
At the heart of the Himalayas, the ongoing conflict between China and India for the hydro-power race will affect the whole region.
How the borrowed concept of gated communities is dividing rich from poor in the Peruvian capital.
On the US-Mexican border.
A recent study shows Donald Trump is out of date when he claims "people are pouring across our southern border".
Stand-off: Colombian and Venezuelan police at the border.
With drug trafficking, turf war, and craven politicking all at work, Colombia and Venezuela's fraught relationship has taken a turn for the worse.
New world, new customs.
As the world waits to hear what turn the Ukraine crisis takes next, it is wise for business leaders to stop and think about the questions raised by this unexpected clash of great powers. Some will worry…