Next up in the series of posts on Google AdSense ad sizes are the ads in the Google Adsense “Other – Vertical” banner category, starting with the 120×600 skyscraper. The reason the ad unit is called a skyscraper is because it is tall and thin and can dominate the space, like an actual, physical skyscraper. This ad unit is not in the AdSense top 4 recommended sizes and is listed in the Delisted Standard Ad Units category of the Interactive Advertising Bureau (IAB) Ad Unit Guidelines. Microsoft Advertising, however, continues to list the 120 x 600 – Skyscraper as part of its standard ad unit sizes, both for marketers and agencies, as well for small and medium businesses.
The original skyscraper was thinner than the current commonly used version of the skyscraper, to accommodate the small side rails in the layouts of many web sites. As site design has changed and elements, including sidebars, of site layouts have gotten larger, the Google AdSense 160×600 Wide Skyscraper has become the more prominently used ad unit.