For Kathy Latrobe, family reunions tend to be a bit more complicated than noodle salad and group pictures.

That’s because when you’re the great-great-great-granddaughter of Benjamin Henry Latrobe — often referred to as America’s first professional architect and one of the original designers of the Capitol Building — you don’t just hold reunions, you hold international symposiums.

This year’s Latrobe International Symposium, which takes place this week, has brought together more than 60 Latrobe descendants from around the United States and as far away as England, France, Germany, South Africa and Australia. On Wednesday, the group traveled to Capitol Hill for a personal tour with William Allen, architectural historian for the Architect of the Capitol, to see the legacy of their famous ancestor.

They are a group that is extremely proud of where they come from. Both young and old can quote chapter and verse on Latrobe family history and give tidbits of trivia about their famous relatives. For instance, Kathy Latrobe points out that Benjamin Henry Latrobe technically should be referred to as

B. Henry Latrobe, the way the architect preferred to sign his name professionally.

As he sat eating his boxed lunch in the Cannon House Office Building on Wednesday, John Latrobe explained that the family can trace its roots back to France in the early 1400s. Around him a mixture of English and French can be heard as three generations of Latrobe descendants discuss their earlier stops at the Washington Navy Yard and the National Arboretum where Benjamin Henry’s influence can still be seen.

But, in some ways the gathering is no different than any other family get-together.

“Can you see that we all have the same nose?” joked Brian La Trobe, who hails from the South African branch of the family, as he pointed around the room to all his distant cousins. La Trobe is one variant of the spelling of the family’s name.

Kate Torode, one of the British Latrobes, excitedly pointed out that this week she’s met a family member who, if one were to trace the lineage back, would technically be her 19th cousin — give or take a one or two times removed.

About half the group are direct descendants of Benjamin Henry, while the rest trace their roots to other Latrobe branches such as the American architect’s brother, Christian Ignatius, who was a missionary to South Africa for the Moravian Church.

And if any of the genealogy gets confusing, family members can always just consult the official family tree, which is brought to every official Latrobe symposium. The mammoth research project took years to create and currently includes some 6,000 individual family members and spans 17 generations.

The first Latrobe symposium was held in Paris in 1997 after research efforts by individual family members in the 1980s and 1990s began uncovering and connecting the various branches of the Latrobe tree. The second symposium was held in England in 2001, and plans are already in the works to hold the next symposium in Australia, where one famous Latrobe was the first superintendent of the colony of Port Phillip, which would later become the state of Victoria.

“After the first symposium, people not only built friendships but became so interested in learning about the whole family that we decided to do it again,” Kathy Latrobe said. “This time, the big interest really is Benjamin Henry and his sons, who became very prominent in Baltimore.”

She said the weeklong symposium has been in the works for about two years. In addition to the Capitol tour, the family will visit Benjamin Henry’s Basilica of the National Shrine of the Assumption of the Blessed Virgin Mary in Baltimore and hear lectures on how the Latrobe family helped build the Baltimore and Ohio railroad. Along with Allen, a half-dozen other historians and university professors are scheduled to address the group this week.

When he entered the room, Allen welcomed the “distinguished descendants of one of the premier architects of the Capitol.”

He gave a brief history of Benjamin Henry’s work on the Capitol before gathering the group together for a special tour that included opening up the Old Senate Chamber.

Allen explained that Benjamin Henry was actually the fourth architect hired to build the Capitol but is also sometimes referred to as the second official Architect of the Capitol.

Benjamin Henry is credited with introducing the Gothic and Greek Revival styles of architecture to America. In 1803 he redesigned the south wing of the Capitol and also rebuilt part of the north wing. After the British burned the Capitol in 1814, Benjamin Henry was appointed to oversee the necessary restoration work. His greatest achievements in the Capitol include Statuary Hall, the Old Senate Chamber and the Old Supreme Court Chamber.

As they made their way through the Capitol Building, Allen made sure to point out the Latrobe display case in the Crypt of the Capitol. He then led the group upstairs and into the Old Senate Chamber, where he explained how Benjamin Henry created a design that accommodated both the public and working Members. He stopped intermittently as family members translated his history lesson into French before explaining how Latrobe’s ideas spread across America and influenced the design of a number of state capitals.

“These symposiums give us a great sense of family,” said Brian Latrobe, smiling. And as the group made its way past hundreds of visitors milling about the halls of the Capitol yesterday, one wonders how many others could say that their ancestors had a hand in designing the very floors and halls the busy tour guides were taking questions about.

“We’re all very, very proud,” Brian La Trobe said.