He also revisited many other themes from his campaign: building a border wall, repealing and replacing Obamacare, ensuring border security and assailing the Obama administration and Democrats as weak leaders while touting "100 days of devotion hard work and love for our country."
Trump's remarks were interrupted by several protesters, and as had been the case during some campaign rallies, he paused his speech and told security officials to "get 'em out."
"There's no place I'd rather be than right here in Pennsylvania," Trump told the crowd in Harrisburg.
"They are gathered together for the White House Correspondent's Dinner -- without the president. And I could not possibly be more thrilled than to be more than 100 miles away from Washington's swamp, spending my evening with all of you."
He went on to call the media "a disgrace" and "incompetent."
Trump said that many journalists are "trapped at the dinner, which will be very, very boring," but he suggested that he could "make it more interesting" next year by showing up.
He praised the work that he and his administration have done on a series of issues, from immigration and border security to bringing back jobs, making specific references to coal mining jobs in Pennsylvania.
"We have ended the war on beautiful, clean coal and we are putting our miners back to work. We love our miners," Trump said.
"We are keeping one promise after another and frankly the people are really happy about it. They see what's happening, but to understand the historic progress we have made we must speak honestly about the situation we and I inherited, because -- believe me -- the previous administration gave us a mess," he said.
Tonight's rally was reminiscent of many of Trump's campaign rallies, with him pausing to enjoy chants from the crowd, commenting on posters -- including one that read "Blacks for Trump" -- and reading a poem called "The Snake" that was a regular feature of his campaign events.
He was introduced by Vice President Mike Pence, who touted the administration's accomplishments.
"In just 100 days, President Trump has turned America around and he's just getting started," Pence said.
The rally ended with the Rolling Stones' "You Can't Always Get What You Want" -- a song that typically ended Trump's rallies.