The second most popular month was October when there were more than 30,000 hits.
In the previous year there were 350,000 hits to restricted websites.
In the previous year there were 350,000 hits to restricted websites.
Jonathan Isaby, Chief Executive of the Taxpayers' Alliance, said: “Some of these 'visits' are no doubt the product of pop-ups beyond anybody's control, but the number is absolutely staggering.
David Cameron previously vowed to block hardcore porn from "the darkest corners of the internet".
In 2013 he said: "For a lot of children, watching hardcore pornography is in danger of becoming a rite of passage.
"I will do whatever it takes to keep our children safe." he said.
In 2013 he said: "For a lot of children, watching hardcore pornography is in danger of becoming a rite of passage.
"I will do whatever it takes to keep our children safe." he said.