Where: Gresham College
This university was founded in 1597 by one Sir Thomas Gresham, who also established London's Royal Exchange. They host over a hundred lectures a year, free for all to attend. The topics generally have a historical focus, but it's fair to say there's something for everyone, from the history of sourdough bread to lectures on feminism, mathematics, and the stories of acclaimed classical musicians. The uni is located just off Holborn in Barnard's Inn, a 13th century building that was previously a law school. Make sure you register for tickets early as they go fast.