Italian neighbors used to compete by building tall towers. See inside one that's still standing after 600 years.

The 150-foot-tall Torre Guinigi dominates the skyline in Lucca, a city in Tuscany, Italy.

The medieval tower, an example of Romanesque-Gothic architecture, was built in the late 14th century for a family of wealthy merchants and bankers, the Guinigis. It was part of a complex of buildings where members of the family lived, according to the tower's visitor website.

At one point, the city had more than 130 towers. Today, according to the city's tourism office, Torre Guinigi is one of just two towers dating back to the Middle Ages.

At the time it was built, neighbors competed to see who could build the tallest structure.

It was common in Italy for rich families to commission towers to see who could build the tallest one.

"Towers were symbols of power, of importance, prestige, and wealth," MP Tours founder Paula Stanghetta, who has visited the city, told Business Insider. "Families competed to create the highest, most unique tower, which could also serve as a strategic advantage in times of attack."

However, by the 16th century, most of the towers had been destroyed or reduced in size. Others fell because they simply couldn't withstand their heights.

"Beyond a certain height, however, the tower often collapsed, to the mockery of the owner and great satisfaction of the enemy families," wrote Lucca's tourism office.

Torre Guinigi is now open to the public. To reach the roof, visitors must climb 230 steps.

The tower remained in the Guinigi family until 1968, when descendants bequeathed it to the city, according to the tower's visitor website. It was restored and opened to the public in the 1980s.

Now, visitors can climb 230 steps over 28 flights of stairs to reach the top. The stairs were originally on the outside of the building.

It costs 6 euros to visit, or around $6.50.

Once at the top, visitors will find panoramic views and one of the most unique gardens in the world.

When the Guinigi family built the tower, they created a garden on the roof to "represent rebirth and renewal," according to Tuscany's tourism office.

Today, holm oak trees, which are native to the Mediterranean and common in Italy, shade visitors from the Italian sun.

"Its garden and height are what make it unique," Stanghetta said of Guinigi Tower. "And of course there is a legend or tragic story that is connected to the garden."

The legend goes that the garden's tallest tree was planted by Paolo Guinigi, who became the lord of Lucca in 1400. In 1430, a popular revolt ended his leadership, and he was arrested. Before his death, while he was imprisoned in 1432, the tree at the top of the tower is said to have lost all of its leaves.

From the top of the building, visitors can see the one other remaining medieval tower in Lucca: the 160-foot-tall Torre delle Ore.

The Torre delle Ore, a clock tower, is the tallest tower in the city, according to Lucca's tourism office. It has held a clock since 1390.

From the top of Guinigi Tower, visitors also look out on the city's red roofs, its original Roman center, church spires, and the Tuscan hills.

Centuries after they built the structure to flaunt their wealth, the Guinigi family's tower endures.

The structure, one of the most popular attractions in Lucca, offers a fascinating insight into how Italy's wealthy classes once operated.