The glass building affectionately known as the “Gherkin,” at 30 St. Mary Axe, is among 500 of London’s contemporary or historic buildings open to the public Sept. 18-19, 2004. Called London Open House, the free event includes access to private homes, arts spaces, offices, banks, government buildings and the new Wembley Stadium. Phone 020 7267 7697, fax 020 7267 2822 or visit www.londonopenhouse.org.