Located within the heart of Rome sits the smallest country in the world. The population of Vatican City is a mere 831. Most of these residents are priests and nuns, working closely with the head of the Catholic Church, but 22 of the Vatican City citizens are children. That’s because tucked away behind St. Peter’s square, 110 Swiss Guards live with their families within the walls of Vatican City.

Now, an exclusive new tour gives visitors a glimpse of what life is like for the small group of soldiers entrusted with guarding the Pope and the sovereign state.

The recognizable Swiss Guards are a modern day mainstay of Vatican City. Their bright uniforms and intimidating halberds make their presence around the Vatican hard to miss.

The tradition of Swiss soldiers guarding the Pope began in 1506 when Pope Julius II recruited mercenaries from Switzerland to protect Vatican City. The true test of loyalty came on May 6, 1527 when 147 Swiss soldiers were slain protecting the Pope during the Sack of Rome. The surviving group of 42 guards whisked then-Pontiff Pope Clement VII to safety by making use of the secret passages that connect the Vatican to Castel Sant’Angelo.

In commemoration of that courageous battle, new Swiss Guard recruits are always sworn in on May 6th. Taking the oath in May is the last step in the long process of becoming a member of the elite group.

New recruits must be between 19 and 30 years old. They must be Roman Catholic Swiss citizens with Swiss military training. Hopefuls must also be at least 5’7’’ (174 cm) and unmarried. Once joining the ranks, guards serve at least two years, and are welcome to extend their service up to 25 years.

The Swiss force guards the Vatican’s four entrances and is charged with ensuring the Pope’s personal safety. The guards work long shifts, round the clock, and so are always close at hand and live in apartments within Vatican City.

Normally only open to the guards and their families, a new tour offers a rare opportunity to visit a part of Vatican City traditionally closed to visitors.

Roman Empire Tours takes groups through the Vatican museum and the Sistine Chapel, ending with an exclusive opportunity to explore the Swiss Guard barracks.

The tour takes visitors within the quarters of the world’s smallest army. After an introduction, the group moves into the armory to see the uniforms and weapons up close.

Legend has it that Michelangelo designed the Swiss Guard uniforms, but the current military dress was actually created in 1914 by Jules Repond. A single uniform is made of 154 pieces and must be custom tailored for each guard, so each suit hanging near the armory will have an individual soldier’s name pinned to it.

The tour of the armory offers a glimpse at the history of Swiss Guard weapons. Visitors will learn about the evolution of arms used by the elite forces. The barracks have a weaponry timeline that features maces, swords and firearms, but today’s Swiss Guards rely more on unarmed combat.

After inspecting the traditional armor that is still worn on ceremonial occasions, the group can catch an outside glimpse of where the Pope retires every night. The windows of the Papal apartment and library are clearly visible from within the Guards’ quarters.

The tour of the museum and barracks takes approximately four hours and costs €50 per person. The charming Irish guides offer an engaging tour and an uncommon look at the Vatican that few people ever have the chance to experience.