Millions people al over the world spend their holidays visiting museums and art galleries. They visit them to see new things, to know more about other countries, their traditions, about history and even future of the mankind. There are different types of museums: historical, military. The Tower of London is a historical museum. It is the oldest palace, fortress and prison in Europe. It’s also one of the most popular museums nowadays. The great central tower, the White tower was built around 1090 by William the Conqueror on the site of a Roman fort built there more than 1000 years earlier. Massive defensive walls and other towers were added later. Through the centuries, the Tower of London has been a citadel, a palace, a prison for offenders against the State, the home of the Mint, the treasury for the Crown Jewels, a menagerie, and the first Royal observatory. Three queens of England have been beheaded within its walls. The Tower’s guardians are the Yeomen Warders who wear splendid scarlet and gold uniforms dating back to Henry VII’s time. Sir Hans Sloane was a great collector. He filled his house with rare books and pictures, precious stones, stuffed animals, birds and butterflies, and ancient remains from all over the world. There had never been a collection quite like it , and visitors were amazed by what they saw. When Sir Hans Sloane died in 1753, his wife let the King buy the whole collection for just 20 000 pounds so that it could belong to the nation forever. This was the start of the British Museums. It took thirty years and thousands of tons of stone to complete the building and the forty-four massive columns, which decorated the front. The building of the British Museums was finished in 1948. The state Tretyakov Gallery is one of the best-known picture galleries in the world. It takes its name from its founder Pavel Tretyakov, a Moscow merchant and art connoisseur. In the mid-19th century, Tretyakov began to collect Russian paintings. He visited all the exhibitions and art studios and bought the best pictures of contemporary artists. Little by little Tretyakov extended his range of interest and began to collect earlier Russian paintings. More than once he had to add wings to his house, because his collection grew larger and larger. In 1881 Pavel Tretyakov opened his collection to the public. 11 years later he donated it to the city of Moscow. Since then the gallery has received hundreds of pictures from other museums and private collection. Today the Tretyakov gallery is not only Russia’s biggest and most important museums of Russian art, it is also a research, cultural and educational center.