John Prosser had an oracle-like ability to predict that Denver would become the city it is today, but he made it a major part of his lifeâs work to ensure the historic fabric of the city wasnât lost amid massive population increases and the waves of development that followed. âBelieve me,â he said in 2001 as the U.S. census showed Coloradoâs population density rapidly rising, âyou ainât seen nothing yet.â Those efforts by the urban planner and architect left his fingerprints all over Denver, from Lower Downtown to the airport and the Auraria Campus to the Denver Tech Center. The long-time University of Colorado Denver professorâs latest focus was pushing back against state plans to reconstruct Interstate 70 through the impoverished neighborhoods of northeast Denver. âIf you look back over the last four or five decades, itâs really hard to imagine and to understand the big impact that he had,â said Denver developer and preservationist Dana Crawford, who knew Prosser for more than 60 years and had lunch with him hours before he died. âNot only on the school, but on the special projects that he worked on.â Prosser died Monday at 84 following a stroke, according to family, leaving behind a somewhat hidden legacy for which he never asked for thanks. âHe wanted to do whatever he could to take care of other people and did it with absolutely no ego,â said his daughter, Jenn Anya Prosser. âMy dad was the most dedicated person Iâve ever met. Itâs something Iâve kind of taken for granted my entire life â I grew up knowing I was John Prosserâs daughter and that meant things I didnât fully understand.â The Wichita, Kansas, native was an Air Force veteran and world traveler who piloted bombers, was a top-notch golfer and a father, grandfather and husband. But he was also a fierce protector of Denverâs past, helping preserve buildings (like the Tivoli Brewery and St. Cajetanâs Church) when the Auraria Campus was built and working on projects like the University of Colorado Anschutz Medical Campus and Denver Botanic Gardens. Most recently, he had been one of those leading the charge against the Colorado Department of Transportationâs overhaul of I-70, calling for the highway to be rerouted to the north and the reunification of neighborhoods split by the roadwayâs original construction. (The controversy has gained national attention and stoked a surge of activism.) âJohn was a history book,â said Denver community organizer Bridget Walsh, a fellow opponent of the I-70 project. âHe had lived a long enough time to see ideas come and go. John was one of the first people to ring the bell on I-70 as being a boondoggle.â That activism and selflessness translated too into his family life and work as an educator. âWhen my car would get plowed into a spot, my dad would come pick me up at 5:30, 6 in the morning and drive me to work and then go back and shovel out my car. At 82,â Jenn Anya Prosser said. âHe just got better with age. He was such a caring person.â âMy dad worked with CU for over 40 years,â said Anne Prosser, another of Prosserâs five children. âHe loved being an educator. I think he just always saw the potential in people and believed in people.â Crawford, who worked with Prosser on development and preservation projects in places like Lower Downtown Denver, said when she had lunch with her old friend from the University of Kansas hours before his fatal stroke, âhe was just completely vital and had an idea a minute as usual.â Prosser shared with her seven words to live by that came from a book he was reading. âThe words are âBe healthy. Be kind. Respect the environment,â she said. A celebration of Prosserâs life was held at 4 p.m. Saturday at the Oxford Hotelâs Sage Room, 1600 17th St., Denver. It is open to the public.