I undertook work experience with a Member of Parliament in June 2006, so had the chance to see David Cameron debate Tony Blair in the House of Commons. In March 2015 I was invited to visit again, this time taking more time to appreciate the oldest part of the building, Westminster Hall. This was where from the 11th century the earliest parliaments were called by the monarch, usually when he needed to raise a tax to pay for a war.
We paid the ridiculous £18 per person charge to enter Westminster Abbey in April 2015. Although not a cathedral, it is as grand as any in the land and more important than most. The East Face can be appreciated for free from the outside, but you must go inside to see the tombs of many an important monarch or historical figure (including Henry VII, Richard II, Elizabeth and Mary).
The smaller St Margaret’s Church next door is free to enter and a lot quieter. Since Westminster Abbey was originally a Benedictine Abbey, a church was required for the day-to-day worship of parishioners in Westminster.