If you had told someone a century ago that penthouses would become some of the most sought after, but also expensive types of homes in the world, they would probably have laughed heartily. And rightly so, considering the fact that in those days there were no more than dirty, uninhabitable rooms, in which the laundries were arranged, or which served as storage space for construction materials. Few would have ventured to the top floor of the buildings, especially since the newly invented elevators did not yet offer today's safety.

The genesis of penthouses, as we know them today, is closely linked to New York City. At the beginning of the twentieth century, in the post-war period, wealthy New York families found a new use, turning them into resting rooms for servants, driven by the need to maximize space, amid the economic boom followed by a growing population and, naturally, higher demand for housing.

After 1920, however, the penthouses would break new grounds when the rich but eager for a bohemian life Americans, noticing their potential, gave them a new shine. Soon, romance and intimacy, as well as the unique views they offered began to attract increasing interest. The architects did not waste time, transforming the old dirty corners into bright houses with green terraces – oases of peace in which artists could find inspiration while having the bustle of the city at their feet.

The term penthouse is said to have been first used by writer Steven Ruttenbaum in the biography of architect Emery Roth, who built the 15-story twin towers Myron Arms and Jerome Palace in New York in 1922-1923, hosts to the new types of homes whose fame grew every day.

One of the most luxurious penthouses built at the time was designed two years later in Manhattan, on Fifth Avenue. With no less than 54 rooms, a panoramic terrace, 17 bathrooms, two kitchens, and a living room that could accommodate up to 125 guests, the apartment has become a symbol of luxury and opulence. It was arranged at the request of the "grain empire" heiress, Marjorie Merriweather Post, the daughter of the founder of Post-Consumer Brands. The penthouse was her condition for agreeing to give up the mansion she owned to build, in its place, a 14-story building.

Since then, the penthouses have spread to all continents and adapted to new architectural trends, maintaining their status as exclusive, top homes.

Trends in the design of some of the world's most luxurious penthouses in recent years include the use of luxury materials such as marble and natural stone, rural accents, ambient lights, pools, and fireplaces, as well as pergolas – necessary to admire the views regardless of the season, accompanied by comfortable seating areas and green spaces.

Almost a century later, also in New York, we find one of the most luxurious penthouses in the world: 51/52W, designed in one of the most impressive housing complexes in the city, Bloomberg Tower. The duplex has an area of about 800 square meters, five bedrooms, and an impressive view, which can be admired from the inside through windows over 3.6 meters high.

Another example comes from Singapore: Wallich Residence, the highest residential development in the country, which is actually a collection of 181 apartments, including a penthouse located on floors 62-64 of the building. It is distinguished by its all-glass walls, a huge living room, a billiard room, a swimming pool, and a roof garden, all highlighted by an intelligent lighting system.

Europe also boasts iconic penthouses, such as The Heron, housed in a 36-story building in central London. The 550-square-meter duplex with marble floors has four bathrooms, four bedrooms, a Boffi kitchen, and a central room with a retractable ceiling.

Romania is also gaining ground in this niche. Successful examples are the penthouses in One United Properties portfolio, in projects such as One Floreasca Lake, One Herăstrău Park, One Mircea Eliade, One Verdi Park, or One Peninsula. As an example, the penthouse located on the top floor – 20 – of One Mircea Eliade residential complex has, among other things, a 9-meter long and 3-meter wide swimming pool set right in the living room, luxury furniture, and exclusive design, complemented by a 360-degree view of the city.

Data for this article was obtained from: faena.com, veranda.com, christiesrealestate.com, and luxhabitat.ae.