Located in Sinaia (44 km from Brasov), Peles Castle is considered by many one of the most beautiful castles in all Europe. It was the final resting place for several Romanian monarchs including King Carol I, who died here in 1914.

The building of the castle began in 1873 under the direct order of the Viennese architect Wilhem Doderer and was continued in 1876 by his assistant, Johann Schultz de Lemberg. During 1877-1879 because of the war they abandoned work. That's why the castle was inaugurated only on October 7, 1883. The location for the castle was chosen by the German prince Carol I de Hohenzollern, who was to become a king and it draws its name from the neighboring brooks which passes through the courtyard.

Several other buildings, annexed to the castle, were built simultaneously: The Guard's Chambers, The Economat Building, The Foisor Hunting House, The Royal Stables, and the Electrical Power Plant. The Sipot Villa was constructed later. This would serve as the work site of architect Karel Liman. Liman would later supervise the building of Pelisor (1889-1903, the future residence of King Ferdinand and Queen Mary of Romania). as well as of the King's Ferdinand Vila in the Royal Sheepfold Meadow

The castle was built in wood, stone, bricks and marble and comprises more than 160 rooms. The representative style used is German Renaissance, but one can easily discover elements belonging to the Italian Renaissance, Gothic, German Baroque and French Rococo style.

King Carol I of Romania (1839–1914), under whose reign the country gained its independence, first visited the site of the future castle in 1866 and fell in love with the magnificent mountain scenery. In 1872 the Crown purchased 1,300 square kilometres (500 sq mi) of land near the Piatra Arsă River. The estate was named the Royal Estate of Sinaia. The monarchy commissioned the construction of a royal hunting preserve and summer retreat on the property, and the foundation was laid for Peleș Castle on 22 August 1873. Several auxiliary buildings were built simultaneously with the castle: the guards' chambers, the Economat Building, the Foişor hunting lodge, the royal stables, and a power plant. Peleș became the world's first castle fully powered by locally produced electricity.

The first three design plans submitted for Peleș were copies of other palaces in Western Europe, and King Carol I rejected them all as lacking originality and being too costly. German architect Johannes Schultz (1876–1883) won the project by presenting a more original plan, something that appealed to the King's taste: a grand palatial alpine villa combining different features of classic European styles, mostly following Italian elegance and German aesthetics along Renaissance lines. Later additions were made between 1893 and 1914 by the Czech architect Karel Liman, who designed the towers, including the main central tower, which is 66 metres (217 ft) in height. The Sipot Villa, which served as Liman's headquarters during the construction, was built later on. Liman would supervise the building of the nearby Pelişor Chateau (1889–1903, the future residence of King Ferdinand I and Queen Marie of Romania), as well as of King Ferdinand's villa in the Royal Sheepfold Meadow.

Peles is surrounded by seven terraces decorated with statues (sculptured by the Italian, Romanelli), stone-made-wells, ornamental vases and Carara marble. The architects used an abundance of wooden decoration, both for the exterior and for the interior of the castle, which confers a very special quality to the building.

Quite outstanding are the Big Armory Room, the small Armory Room, the Florentine Room, the Reception Room (where paintings and wooden sculptures depicting 16 castles of the Hohenzollerns are exhibited), the Moresque Room, The French Room, the Turkish Room, the Council Room, the Concert Room as well as the Imperial Suite.

Other exquisite attractions such as the statues, the ceramics, the gold and silver plates, the Meissen and Sevres porcelain, the Murano crystal chandeliers, German stained-glass windows, walls covered with Cordoba leather, ebony and ivory sculptures, as well as the extensive weapon collections are worth mentioning. It is also important to know that Peles Castle shelters one of the most important and most valuable painting collections in Europe, almost 2.000 pieces.

Almost adjacent to Peles Castle is Pelisor ("Little Peles"). King Ferdinand, who succeeded Carol I, intended to use Peles Castle as a summer residence. Supposedly he found Peles too big and overwhelming, so he commissioned the smaller, art-nouveau style, Pelisor Castle. Pelisor's 70 rooms feature a unique collection of turn-of-the century Viennese furniture and Tiffany and Lalique glassware.

Near Peles castle there is Foisor, a kings' residence with 42 rooms designed in the Swiss style. By form and function, Peleş is a palace, but it is consistently called a castle. Its architectural style is a romantically inspired blend Neo-Renaissance and Gothic Revival similar to Schloss Neuschwanstein in Bavaria. A Saxon influence can be observed in the interior courtyard facades, which have allegorical hand painted murals and ornate fachwerk similar to that seen in northern European alpine architecture. Interior decoration is mostly Baroque influenced, with heavy carved woods and exquisite fabrics. Peleş Castle has a 3,200-square-metre (34,000 sq ft) floor plan with over 170 rooms, many with dedicated themes from world cultures (in a similar fashion as other Romanian palaces, like Cotroceni Palace). Themes vary by function (offices, libraries, armories, art galleries) or by style (Florentine, Turkish, Moorish, French, Imperial); all the rooms are extremely lavishly furnished and decorated to the slightest detail. There are 30 bathrooms. The establishment hosts one of the finest collections of art in Eastern and Central Europe, consisting of statues, paintings, furniture, arms and armor, gold, silver, stained glass, ivory, fine china, tapestries, and rugs. The collection of arms and armor has over 4,000 pieces, divided between Eastern and Western war pieces and ceremonial or hunting pieces, spreading over four centuries of history. Oriental rugs come from many sources: Bukhara, Mosul, Isparta, Saruk, and Smirna. The porcelain is from Sèvres and Meissen; the leather is from Córdoba. Perhaps the most acclaimed items are the hand-painted stained glass vitralios, which are mostly Swiss.

A towering statue of King Carol I by Raffaello Romanelli overlooks the main entrance. Many other statues are present on the seven Italian neo-Renaissance terrace gardens, mostly of Carrara marble executed by the Italian sculptor Romanelli. The gardens also host fountains, urns, stairways, guarding lions, marble paths, and other decorative pieces.

Of the 168 rooms in the castle, only 35 are accessible to the public. Only the museum in the basement and the rooms on the first floor can be visited. Admission is charged, and there is an additional photography fee. The visiting hours are from 9 a.m. to 5 p.m. Wednesday through Sunday. On Tuesdays the hours are 11 a.m. to 5 p.m. The castle is closed on Mondays. These visiting hours are subject to change by the Romanian Culture Ministry. The castle is closed in November each year for maintenance and cleaning.

The most notable grand rooms are:

Holul de Onoare (The Honor Hall) was finished completely only in 1911, under the guidance of Karel Liman. It spreads over three floors. Walls are dressed in exquisitely carved woodwork, mostly European walnut and exotic timbers. Bas-reliefs, alabaster sculptures, and retractable stained glass panels complete the decor.

Apartamentul Imperial (The Imperial Suite) is believed to be a tribute to the Austrian Emperor Franz Joseph I, who visited the palace as a friend of the Romanian Royal Family. Hence, decorator Auguste Bembe preferred the sumptuous Austrian Baroque in style of Empress Maria Theresa. A perfectly-preserved five-hundred-year-old Cordoban tooled leather wall cover is the rarest of such quality.

Sala Mare De Arme (The Grand Armory or The Arsenal) is where 1,600 of the 4,000 pieces of weaponry and armor reside. One of Europe's finest collection of hunting and war implements, timelined between 14th and 19th century, are on display. The king added pieces used in his victory against the Ottoman Turks during the War of Independence. Famous are the complete Maximilian armor for horse and rider and a 15th-century German "nobles only" decapitation broadsword. Also on display are a wide array of polearms (glaives, halberds, lances, hunting spears), firearms (muskets, blunderbusses, snaphaunces, flintlocks, pistols), axes, crossbows, and swords (rapiers, sabers, broadswords, and many others).

Sala Mica De Arme (The Small Armory) is where predominantly Oriental (mostly Indo-Persian, Ottoman and Arab) arms and armor pieces are on exhibit, many of them made of gold and silver, and inlaid with precious stones. Included are chainmail armor, helmets, scimitars, yataghans, daggers, matchlocks, lances, pistols, shields, axes, and spears.

Sala De Teatru (The Playhouse) is decorated in Louis XIV style, with sixty seats and a Royal Box. Architectural decoration and mural paintings are signed by Gustav Klimt and Frantz Matsch.

Sala Florentina (The Florentine Room) combines revived elements of the Italian Renaissance, mostly from Florence. Most impressive are the solid bronze doors executed in Rome; ateliers of Luigi Magni; and the Grand Marble Fireplace executed by Paunazio with Michelangelo motifs.

Salonul Maur (The Moorish Salon) was executed under the guidance of Charles Lecompte de Nouy, and is meant to embody elements of North-African and Hispanic Moorish style. Mother-of-pearl inlaid furniture, fine Persian Sarouk and Ottoman Isparta rugs, and Oriental weapons and armor are perhaps the most expressive elements. The salon has an indoor marble fountain.

Salonul Turcesc (The Turkish Parlor) emulates an Ottoman "joie de vivre" atmosphere—a room full of Turkish Izmir rugs and copperware from Anatolia and Persia. Walls are covered in hand-made textiles like silk brocades from the Siegert shops of Vienna.