Story highlights Vietnam's first McDonald's restaurant opened this weekend

More than 70 years after it was founded, McDonald's operates in more than 100 countries

But not all of its branches are without controversy: Take a look at some of them

As McDonald's opens its first restaurant in Vietnam , take a look at some of the big breakthroughs the fast food chain has made in the past -- from its first outlet in the Soviet Union, through the Kosher Mac and MacMaharaja, to the branch at Guantanamo Bay.

Russia

It took McDonald's 14 years of intense negotiations to convince the Communist leaders of the Soviet Union to allow the chain to set up their first restaurant. Yet almost as soon as the Iron Curtain began to fall, the first McDonald's opened in Moscow's busy Pushkin Square -- on January 31, 1990.

The restaurant seated 700 diners and its opening attracted thousands of people, who queued for hours to spend the equivalent of weeks' salaries on a single burger.

The company says the Moscow branch is still the largest McDonald's in the world.

Israel

McDonald's operates around 180 branches in Israel, of which over 50 are kosher, meaning they only serve food that meets strict dietary requirements.

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Unlike the non-kosher restaurants, these branches stay closed on Saturdays to observe the Shabbat and boast a unique logo with the golden arches sitting on a blue, rather than red background.

McDonald's restaurants around the world cater to local demands by including their own versions of regional specialties on the menu: in Israel, that's the "MacKebab."

Guantanamo Bay U.S. Navy base

The McDonald's within the compound at Guantanamo Bay naval base is the only branch of the fast food chain on the island of Cuba. The restaurant is only accessible to the base's personnel and the chain says it has no plans to open any other branches in Cuba.

Bosnia and Herzegovina

McDonald's spent more than four years trying to break into the Bosnian market, but opposition from local shop owners, supported by the government, was fierce. The chain finally opened its first branch in the country in 2011.

McDonald's Arabia

McDonald's has managed to succeed in many Middle Eastern countries, offering various culturally- and religiously appropriate specialties to its Muslim customers.

The company's first venture into the Arab world was Morocco, where it opened its first branch in Casablanca in 1992.

Most branches respect Ramadan, restricting service in fasting periods during the holy month, and offering special menus at night.

Certified halal-quality food is widely available, and the restaurant tries to reflect the local tastes by offering the MacArabia Chicken Sandwich, served in folded Arabic bread.

In Saudi Arabia, the chain adheres to local laws by segregating male and female diners -- much to the disapproval of international women's rights organizations

India

The global hamburger chain is a big success in India, where it operates 300 branches.

McDonald's offers special meals to please the palates of local customers; it does not serve any beef or pork-based burgers, reflecting the religious beliefs of many Indians. Instead, it offers the Chicken MacMaharaja and the McAloo Tikki -- a vegetarian-friendly blend of spicy potatoes and peas.

Iraq

OK, it's not really the real deal, but McDonald's could still claim it as a win -- of sorts... As on other U.S. military bases around the world, McDonald's food used to be available within Baghdad's Green Zone.

And while the chain is not planning to expand into the country, a successful knock-off fast food restaurant "MaDonald's" in the town of Sulaymaniyah has been popular with locals since it opened there in the 1990s.