The Royal Ontario Museum, commonly known as ROM, is one of the major museums for world culture and natural science in the city of Toronto. ROM is the largest museum in Canada and the fifth largest in North America. Over six million objects are stored in over 40 galleries. It has a remarkable collection of dinosaurs, Middle Eastern, African and East Asian arts, European history and Canadian history. Inaugurated on March 14, 1914 by Prince Arturo, Duke of Connaught, Governor General of Canada, the original form of the museum was designed by the architects to Frank Darling and John A. Pearson. The architectural style is an Italian neo-Romanesque, very popular in North America in the seventies of the nineteenth century. The structure is strongly massive and bearing surrounded by arched windows and semi-arched, with columns and moldings. The original building was built on the western edge of the property along the university philosophers' promenade, with entrance into Bloor Street. This is the first of the three stages of the museum's expansion to Queen's Park. As the museum grew, it took the form of an H. The first expansion of the ROM was the construction of the wing in front of Queen's Park. Designed by Alfred H. Chapman and James Oxley, for its construction the Argyle house, a Victorian villa at 100 Queen's Park, was demolished. Inaugurated on October 12, 1933, a new grand entrance was added, a neo-Byzantine style mosaic was also created. The expansion required a greater number of men than necessary to be able to give employment during the great depression, the excavation for the bases and the foundations made by hand, with the alternation of team of workers. The new wing was built in the Deco style with rustic stone, triple windows contained within recessed arches, and of different stone colors arranged in a variety of models. The style is common with the other neo-Byzantine style buildings of North America, the facade contains elements of the Gothic style such as bas-reliefs, statues, sculptures and gargoyles. The ceiling is decorated with a round, or rose window, of Byzantine style covered mainly in gold and painted bas-reliefs and glass mosaics, the mosaic is colored with geometric patterns and mythological animals. In the newspaper of the Royal Institute of Architecture of Canada, in 1933, Mathers wrote about the expansion, (The interior of the building is a pleasant surprise, a bit complicated the ornament of the facade is simple, direct and large-scale. One can be convinced that in the rapid design of the Fine Arts, the designer was not in vain.The interior feature is the glass mosaic on the ceiling of the entrance roundabout, which is executed in colors and gold, and strikes a nice note in a part of the building, which the architect's decoration does not conflict with the show.) The original building and the 1933 expansion have been listed in the heritage of Toronto's historic buildings since 1973. Originally, there were five large galleries to the ROM, one each for the archeology, geology, mineralogy, palaeontology, zoology fields. In general, in the museum, many pieces were not classified and the elegant layout had not changed much since Edwardian's time. For example, the insect exhibition, which lasted until 1970, housed insects from all over the world, in long rows of glass, with insects of the same kind arranged inside bulletin boards, with only the name and path of the species and a description can be found. Since 1960, many exhibitions have been set up inside the museum, one of the first was the dinosaur gallery, stabilized in the mid-60s. The fossils of the dinosaurs were placed in dynamic poses against a backdrop of contemporary landscapes. The exhibition has become very descriptive and interpretive, sometimes, as with the mammoth extinction, offers different theories.