With another E3 behind us, game fans are now talking about how 2017 stacked up against previous years’ events. Whether it was better or worse is open for debate, but one element of E3 that’s always a highlight are the pictures on the walls of LA’s Hotel Figueroa.

You’ve probably seen the iconic images before. They’ve featured titles such as GTA V, Skyrim, Max Payne 3, Gwent, Star Wars: Battlefront II, and many more. But, as noted by Kotaku’s Luke Plunkett, many people don’t realize that they’re painted by hand.

Painting ads on the side of the Figueroa is a practice that’s been going on for decades. In recent years it’s been undertaken by a company called Walldogs, which specializes in giant, hand-painted advertisements.

There was a time when LA was populated with companies that worked on massive, hand-painted ads like these, but in the early 1990s the industry started changing over to vinyl computer-printed billboards, which are easier to produce and maintain, and help keep advertising uniform across the country.

Walldogs owner Riley Forsythe admits there are only a handful of firms around today that still hand-paint walls. He says the risk of large pieces of vinyl blowing down, the huge buildings being unable to accommodate a frame, and the appeal of watching people paint keeps his company and others like it in business.

Check out the 2014 Bloomberg interview with Forsythe below, which shows how a project moves from the initial stages to a full-sized wall painting.