From the Seven Kingdoms to Slaver’s Bay, the world of Game of Thrones is full of unique environments, and production designer Deborah Riley has been bringing them to life since season 4. Speaking to The Daily Bruin, Riley talked about her favorite sets and the challenges of working on a show this huge:

There was such a lot to do with just their philosophy of how to get this thing made as well as understanding what the previous production designer had done and how she had established the world. … I found that all to be overwhelming, but I was also just so incredibly impressed by the quality of the work they do. When you walk onto the sets, it really is phenomenal. … It’s just a really immersive environment, and I don’t think I’ve really stood on something so utterly convincing in any kind of world before.

As the person in charge of the entire art department, Riley is the only one in her line who has “a complete, overarching view of the whole show.” Generally speaking, the teams who work in Belfast work in Belfast, the teams who work in Spain work in Spain, etc. That gives Riley a lot of responsibility, as she needs to “to make sure that the art department has everything it needs in order to produce the work that we have to produce.” Considering some of the evocative sets she’s created, from the House of Black and White to Hardhome, it looks like she’s been successful.

But even considering all the sets she’s had a hand in creating, the first set Riley oversaw is still her favorite. “When I started in season four, and we built the Meereen audience chamber, that was a moment that I will remember for a long time,” she said.

It was the first time properly that the season four art department was able to really impact the look of the show. And obviously, as the new production designer, I had a lot of people looking at me and seeing what I would do with the show. … That was my first very strong attempt at doing that and it was a magnificent space to stand in. … It was one of those moments where I really understood the potential of these extraordinary teams of people who work on the show and just what the show is capable of.

Game of Thrones season 7 returns July 16, and if the trailer is anything to judge by, Riley and her crew have topped themselves.