Hong Kong is one of the most densely populated cities in the world, and the photographer who perhaps best captured the crammed and almost impenetrable soul of the city was Michael Wolf.

The award-winning German-born photographer, perhaps best known for his 2009 series titled “Architecture of Density,” passed away in his sleep at his home on the island of Cheung Chau in Hong Kong this week. He was 65.

Born in 1954, Wolf began his career as a photojournalist in Europe and the US before turning his gaze to the more under-appreciated qualities of major cities around the world, including Tokyo, Chicago, and Paris. But he was most fascinated by Hong Kong, where he moved to in 1994, and it was there that he produced his most important body of work.

His last book project, Cheung Chau Sunrises, was published this year, and showcased photos taken over the past two years in Hong Kong from 5:30 to 7:30am each morning.

“He used to look forward to waking up to see the next sunrise and be curious about what would unfold in front of him,” Sarah Greene, director of Hong Kong’s Blue Lotus Gallery, which represented Wolf, told Quartz. “Everyday he would look at the same landscape but yet it would look different everyday. This was Michael in a nutshell, curious about life, art and photography, a sensitive observer who perceived the world like no other.”

Wolf is survived by his wife, Barbara, and son, Jasper.

Below are a selection of Wolf’s photos of his home, Hong Kong.

Michael Wolf, Architecture of Density #91, Hong Kong, 2006. Blue Lotus Gallery.

Michael Wolf, Architecture of Density #91, Hong Kong, 2006. Blue Lotus Gallery.

Michael Wolf, Architecture of Density #99, Hong Kong, 2007. Blue Lotus Gallery.

Michael Wolf, Architecture of Density #79, Hong Kong, 2006. Blue Lotus Gallery.

Michael Wolf, Architecture of Density #31, Hong Kong, 2005. Blue Lotus Gallery.

Michael Wolf, Corner House #39, Hong Kong, 2009. Blue Lotus Gallery.

Michael Wolf, Corner House #34, Hong Kong, 2009. Blue Lotus Gallery.

Michael Wolf, Corner House #24, Hong Kong, 2009. Blue Lotus Gallery.