Twain's party departed Great Falls at 7:35 am, Thursday, August 1st, 1895. They rode the Montana Central Railway, part of the Great Northern Railroad owned by J.J. Hill. Hill needed to connect his interests in Great Falls with the mining operations in Helena, Butte and the smelter in Anaconda. The railroad followed part of the old Mullan Military Road. Along the way we examine the fate of Egbert Malcolm Clarke and one of the most egregious actions taken by the U.S. Army against Native American peoples, the Marias massacre. Twain gave a lecture that evening in Butte. The next day, August 2nd, he and Major Pond traveled to Anaconda. The audience there was so small that Twain reimbursed the local manager one hundred dollars. He was a man Twain had known in the 60's. They returned to Butte and from there to Helena. Monday, August 5th, Twain's party, along with Senator Sanders and Mrs. Henry Ward Beecher rode to Missoula, Montana. They traveled on the Northern Pacific Railroad. Twain entertained and was entertained by the troops at Fort Missoula. From Missoula they continued on to Spokane, Washington. 

https://twainsgeography.com/content/section-4-rocky-mountains