A separation barrier or separation wall is a barrier, wall or fence, constructed to limit the movement of people across a certain line or border, or to separate peoples or cultures. A separation barrier that runs along an internationally recognized border is known as a border barrier.
The Saudi–Yemen barrier is a physical barrier constructed by Saudi Arabia along part of its 1,800-kilometer (1,100 mi) border with Yemen. It is a structure made of pipeline three metres (10 ft) high filled with concrete, acting as a "security barrier along sections of the now fully demarcated border with Yemen" and fitted with electronic detection equipment.
The Mexico–United States border wall is a series of vertical barriers along the Mexico–United States border intended to reduce illegal immigration to the United States from Mexico. The barrier is not a continuous structure but a series of obstructions variously classified as "fences" or "walls".
The Melilla border fence forms part of the Morocco–Spain border in the city of Melilla, one of two Spanish cities in north Africa. Constructed by Spain, its stated purpose is to stop illegal immigration and smuggling. Melilla's border and its equivalent in Ceuta, also bordering Morocco, are the only two land borders between the European Union and an African country.
Illegal entry is the act of foreign nationals arriving in or crossing the borders into a country in violation of its immigration law. Human smuggling is the practice of aiding people in crossing international borders for financial gain, often in large groups. Human smuggling is associated with human trafficking. A human smuggler will facilitate illegal entry into a country for a fee, but on arrival at their destination, the smuggled person is usually free. Trafficking involves physical force, fraud, or deception to obtain and transport people, usually for enslavement or forced prostitution.
The Egypt–Israel barrier or Egypt–Israel border fence refers to a separation barrier built by Israel along its border with Egypt. Initial construction on the barrier began on 22 November 2010, and its original purpose as a common fence was to curb the large influx of illegal migrants from African countries into Israel. However, in the wake of the Egyptian Crisis after the 2011 Revolution, Israel's southwestern border with Egypt experienced an increase in militant jihadist activity with the outbreak of the Sinai insurgency. In response, Israel upgraded the steel barrier—called Project Hourglass by the Israel Defense Forces (IDF)—to include cameras, radars, and motion detectors. In January 2013, construction on the barrier's main section was completed; the final section was completed in December 2013.
The China–North Korea border is an international border separating China and North Korea, extending from Korea Bay in the west to a tripoint with Russia in the east. The total length of the border is 1,352 kilometers (840 mi). The current border was created by two secret treaties signed between China and North Korea in 1962 and 1964.
The Afghanistan–Pakistan border barrier refers to the border barrier being built by Pakistan since March 2017 along its border with Afghanistan. The purpose of the barrier is to prevent terrorism, arms, and drug trafficking, as well as refugees, illegal immigration, smuggling and infiltration across the approximately 2,670-kilometre-long (1,660 mi) international border between Afghanistan and Pakistan.
In 2015, Hungary built a border barrier on its border with Serbia and Croatia. The fence was constructed during the European migrant crisis, with the aim to ensure border security by preventing illegal immigrants from entering, and enabling the option to enter through official checkpoints and claim asylum in Hungary in accordance with international and European law. The number of illegal entries to Hungary declined greatly after the barrier was finished as it effectively abolished the entry to Hungary.
The Slovenian border barrier was a border barrier constructed by Slovenia in 2015–2016 on its border with Croatia as a response to the European migrant crisis. Both Slovenia and Croatia are European Union members, therefore the barrier was located on an internal EU border; but previously only Slovenia was a member of the free travel Schengen Area, with Croatia joining the area in 2023. In March 2016, Slovenia announced that only migrants who apply for asylum in Slovenia and those with clear humanitarian needs will be allowed to enter Slovenian territory.
The North Macedonia border barrier is a border barrier built by North Macedonia on its border with Greece. It was constructed as a response to the European migrant crisis. The construction of the barrier began in November 2015, modeled similarly to the Hungarian border barrier.
The Bulgaria–Turkey border is a 513 km (319 mi) long international border between the Republic of Bulgaria and the Republic of Turkey. It was established by the Treaty of San Stefano in 1878 as an inner border within the Ottoman Empire between Adrianople Vilayet and the autonomous province of Eastern Rumelia. The current borders are defined by the Treaty of Constantinople (1913) and the Bulgarian–Ottoman convention (1915). The border was reaffirmed by the Treaty of Lausanne ten years later, though Bulgaria was not a party to the latter treaty as it had earlier ceded to Greece that part of its border with Turkey which was modified by the Bulgarian-Ottoman convention.
The Trump wall, commonly referred to as "The Wall", is an expansion of the Mexico–United States barrier that started during the U.S. first presidency of Donald Trump and was a critical part of Trump's 2016 presidential campaign platform leading up to the year's election. Throughout his campaign, Trump called for the construction of a border wall to combat illegal immigration. He promised that Mexico would pay for the wall's construction, by a 20% tariff on Mexican goods, a claim rejected by then-Mexican president Enrique Peña Nieto; all construction relied exclusively on U.S. funding.
The Norway–Russia border barrier is an international border barrier built by Norway on the Norway–Russia border. Construction of the barrier began in September 2016 and took a few months. The intent of the project was to prevent the smuggling and illegal crossing of migrants from the Middle East, mainly from Syria, who have used Russia as a route of entry into Norway.
The Greece–Turkey border is around 200 kilometres (120 mi) long, and separates Western Thrace in Greece from East Thrace in Turkey.
The Turkish migrant crisis, sometimes referred to as the Turkish refugee crisis, was a period during the 2010s characterised by a high number of people migrating to Turkey. Turkey received the highest number of registered refugees of any country or territory each year from 2014 to 2019, and had the world's largest refugee population according to the United Nations High Commissioner for Refugees (UNHCR). The majority were refugees of the Syrian Civil War, numbering 3.6 million as of June 2020. In 2018, the UNHCR reported that Turkey hosted 63.4% of all "registered Syrian refugees."
The Iran–Turkey border is 534 kilometres in length, and runs from the tripoint with Azerbaijan in the north to the tripoint with Iraq in the south.
In August 2021, the government of Belarus began coordinating an influx of migrants, mostly from the Middle East and North Africa, to the borders of Lithuania, Poland and Latvia. Although Belarus denied involvement, both the European Union and independent observers viewed it as hybrid warfare undertaken in response to the deterioration in Belarus–European Union relations following the 2020 Belarusian presidential election and the 2020–2021 Belarusian protests. Between August and December 2021, tens of thousands of unauthorized border crossing attempts were recorded, peaking in October. At least 20 migrants died in the following winter due to the actions of Poland. Attempted border crossings fell sharply the following year, but never returned to their pre-crisis levels. In the spring of 2024, numbers began rising again, although they remain well below those seen in the peak of the crisis in 2021.
On 25 January 2022, Poland began building a border wall on the border with Belarus to prevent illegal immigration in the aftermath of the Belarus–European Union border crisis.
