Heading to Vienna? Avoid reading online reviews before you go. At least that's the advice from the city's official tourist board.

Vienna Tourist Board's has launched a new campaign, Unrating Vienna. Image by Vienna Tourist Board

The Vienna Tourist Board is taking a pop at online ratings with its new ad campaign, 'Unrating Vienna.' Following on from the success of last year's campaign, 'Unhashtag Vienna' - which encouraged travellers to take fewer photos and experience more - 'Unrating Vienna' asks travellers to make their own minds up and explore the city on their own terms.

Using ad posters that feature genuine negative feedback from online users, such as one that describes Schönbrunn Palace’s lawn as "a mess," and another that dubbed the view over Prater Park as "rubbish," the campaign aims to highlight how misleading online reviews sometimes are.

The ad campaign features genuinely negative online reviews. Image by Vienna Tourist Board

"We take a humorous look at the notion that online ratings are not always the right path to take when it comes to looking for relaxation and moments of enjoyment." said Norbert Kettner, the tourist board's managing director. "[The campaign] is intended to make people sit up and think and trigger broader public discussion."

Unrating ads have appeared across London Underground and at digital ads at bus stops. Asking the question, "so who decides what you like?" the campaign calls on readers to actively reflect their choices.

Campaign ads have appeared across London's transport system. Image by Vienna Tourist Board

"Online ratings are a great thing which we ourselves use in our own marketing activities as a tourism destination," said Kettner. "However, we see digitalisation as a cultural tool that people should take advantage of, and not as an end in itself."

According to the Vienna Tourist Board 95% of holidaymakers read at least seven reviews before they book a holiday. But reviews are widely subjective. Take for example, Vienna's Staatsoper. The grand concert hall has 19,725 reviews on Google and an overall 4.7 star rating. However, if you scroll through the reviews long enough, you'll come across a negative one, like this one which describes the building as "ugly."

Unrating Vienna is encouraging travellers to make their own minds up. Image by Vienna Tourist Board

Even if you’re generally considered to be one of the greatest wonders of the world you can’t escape a negative comment. One Google review said of The Great Wall of China: "not very tall. Or big. Just sayin. I kinda liked it."