It is not too large compared to other museums (it is only 1% as large as the neighboring Louvre Museum) and the truth is that you can go through a variety of works in somewhere between 1.5 and 2 hours.
One of the most famous exhibits is Claude Monet's "Water Lilies", which is 100 meters long! The paintings were painted between 1914-1926, inspired by Monet's famous garden in his home in the village of Giverny. The paintings are spread over two elliptical rooms that create a beautiful reflection for visitors and were given as a gift to the French government in honor of the French victory in World War I. Monet specifically requested that his work be presented in an aesthetic and poetic manner in order to offer a haven of calm and thought for the Parisians. They were displayed on the ground floor of the building and were lit up in daylight.
In 1965 it was decided to present the Walter Guillaume collection that includes many Impressionist paintings. Walter Guillaume's collections have accumulated over the years because he is a well known art dealer. The works are unique and reflect the style in the early decades of the 20th century.
In order to display the collection, a second floor was built in the building, and the water lilies were lit with artificial light, despite Monet's request. Today the museum has returned to display it in natural daylight.
During the construction and digging of the basement floor, remains of the city wall of Paris, dating back to the 16th century, were discovered. The wall is now on display in the museum and serves as one of the walls of the new halls. In addition, a lecture hall and a library were built underground.