Melbourne will be hosting the Open House event for the fifth year in July with a record 100 buildings set to open.The event is free and will feature examples of environmentally sustainable design, architectural award winners and historic buildings around the city. 106, 000 people participated in the Open House Melbourne last year and this year there will be a Children's Program and Speakers Series with a Gold Medal Theme.Spokesperson for the event, Robert Larocca said: "The program will feature a range of themes, including: medical facilities, gardens in the sky, residential housing and underground sites. Visitors will learn not just about the history of the Melbourne's built form, but about the city itself." The Open House Melbourne event will take place on the weekend of the July 28 and 29. For information visit openhousemelbourne.org.