He made a highly original use of steel frames and skylights to bring light into the structures, open floor plans, and finely-designed decorative details.

His later major works included the Maison du Peuple/Volkshuis (1895–1899), Brussels' Centre for Fine Arts (1923–1929) and Brussels-Central railway station (1913–1952).

[6] In the years that followed, Horta joined the Central Society of Belgian Architecture, designed and completed three houses in a traditional style, and took part in several competitions.

In 1892, he was named head of the Department of Graphic Design for Architecture at the Free University of Brussels, and promoted to professor in 1893.

[6][7] At this time, through lectures and exhibitions organised by the artists' group Les XX, Horta became familiar with the British Arts and Crafts Movement, the developments in book design, and especially textiles and wallpaper, which influenced his later work.

The interior had a traditional floor plan, due to a limited budget, but the facade previewed some of the elements he developed into the full Art Nouveau style, including iron columns and ceramic floral designs.

[9] In 1894, Horta was elected President of the Central Society of Belgian Architecture, although he resigned the following year following a dispute caused when he was awarded the commission for a kindergarten on the Rue Saint-Ghislain/Sint-Gissleinsstraat in the Marolles/Marollen district of Brussels, without a public competition.

Throughout his life, Horta was greatly influenced by the French architectural theorist Eugène Viollet-le-Duc, whose ideas he completely identified with.

Horta used the technologies of glass and iron, which he had practiced on the Royal Greenhouses of Laeken, to create an interior filled with light and space.

The interior decoration featured curling lines, modeled after vines and flowers, which were repeated in the ironwork railings of the stairway, in the tiles of the floor, in the glass of the doors and skylights, and painted on the walls.

In designating these sites, UNESCO explained: "The stylistic revolution represented by these works is characterised by their open plan, the diffusion of light, and the brilliant joining of the curved lines of decoration with the structure of the building.

Horta had a virtually unlimited budget, and used the most exotic materials in unusual combinations, such as marble, bronze and rare tropical woods in the stairway decoration.

[15] The Hôtel van Eetvelde is considered one of Horta's most accomplished and innovative buildings, because of highly original Winter Garden interior and the imaginative details throughout.

The open floor plan of the Hôtel Van Eetvelde was particularly original, and offered an abundance of light, both horizontally and vertically, and a great sensation of space.

This was a large structure including offices, meeting rooms, a café and a conference and concert hall seating over 2,000 people.

[20] Beginning in about 1900, Horta's buildings gradually became more simplified in form, but always made with great attention to functionality and to craftsmanship.

In its design, Horta used all his skill with steel and glass to create dramatic open spaces and to give them an abundance of light from above.

Its unusual design and layout attracted great interest from the European medical community, and his buildings continue in use to this day.

[6] On Horta's return to Brussels in January 1919, he sold his home and workshop on the Rue Américaine/Amerikaansestraat,[7] and also became a full member of the Belgian Royal Academy.

From this point on, Horta, who had gradually been simplifying his style over the previous decade, no longer used organic forms, and instead based his designs on the geometrical.

[7] In 1910, Horta began working on drawings on his most ambitious and longest running project: Brussels-Central railway station.

[6] The start of construction was seriously delayed due to the lengthy process of purchasing and demolishing over one thousand buildings along the route of the new railway between Brussels' main stations, and then because of World War I.

Construction finally began in 1937 as part of the plans to boost the economy during the Great Depression, before being delayed again by the outbreak of World War II.

Art Nouveau fell out of fashion in the 20th century and many of Horta's buildings were abandoned, or even destroyed, most notably the Maison du Peuple/Volkshuis, demolished in 1965, as mentioned above.

Most notable are the Magasins Waucquez, formerly a department store, now the Belgian Comic Strip Center and four of his private houses (hôtels), which were designated as a UNESCO World Heritage Site in 2000 under the title "Major Town Houses of the Architect Victor Horta (Brussels)":[5] Horta was commemorated on the Belgian 2000 franc banknote issued from 1994 until the introduction of the euro.