Social networking site Facebook hit a staggereing one trillion page views in June 2011, according to data provided by Google’s Ad Planner.

The number of page views of Facebook was ten times that of YouTube, which is at the second spot.

Facebook, which had recently disclosed that it had around 750 million users worldwide, saw 870 million unique visitors in June with a 46.9% reach among all Web surfers. YouTube had a reach of 42.6%.

The top 10 most visited websites in the month of June, according to Ad Planner are: Facebook (870 million), Youtube (790 million), Yahoo (590 million), Live.com (540 million), Wikipedia (460 million), MSN (450 million), Blogspot.com (370 million), Baidu (310 million), Microsoft (280 million), and Qq.com (250 million).

Wikipedia is the only non-advertising entry in the top 10 list. Microblogging site Twitter was No. 14 on the list.

In the UK, Facebook (52% reach), YouTube (36% reach) and BBC (32.5% reach) were at the number one, two and three positions respectively.