This weekend is the annual OpenHouse London where hundreds of interesting buildings across the capital are opened to the public. This is an opportunity to get inside and have a look around some iconic buildings, such as the Gherkin and the Foreign Office.
This is the 20th time the event has been run in London. There are over 750 buildings and more to choose from, including talks by architects, walks and boat tours.
The event only takes place once a year and is highly recommended. You only have today 22nd and tomorrow 23rd of September, so get going!
More information: http://www.londonopenhouse.org/