LONDON -- A woman's exposed bottom is Anissa Kate the Widow XXXprobably the last thing you'd expect to see in a car park.

But that's nonetheless what Twitter user Alice Gray spotted in her gym car park in Cardiff, Wales.

SEE ALSO: People think this infographic about 'childless' female politicians is sexist

UFit gym's advert features an image of a woman's bum alongside the text "there's better things to be stuck behind than the car in front". The ad has prompted a massive social media backlash after people accused it of sexism and objectification.

You May Also Like

Gray wasn't the only one to spot the advert and deem it sexist.

Mashable Trend Report Decode what’s viral, what’s next, and what it all means. Sign up for Mashable’s weekly Trend Report newsletter. By clicking Sign Me Up, you confirm you are 16+ and agree to our Terms of Use and Privacy Policy. Thanks for signing up!

Twitter user @nattylou spotted it along the Cardiff half-marathon route, and complained to the marathon organisers.

People responded to her complaint, stating the ad was "inappropriate".

More Cardiff residents have taken to Twitter to call out the ad.

And others feels the ad may make women less likely to join the gym...

UFit gym did not immediately respond to Mashable's request for comment.