Passage: McKinley's trip to Buffalo was part of a planned ten-day absence from Canton, beginning on September 4, 1901, which was to include a visit in Cleveland to an encampment of the Grand Army of the Republic; he was a member as a Union veteran. The McKinleys stayed in Buffalo at the Milburn House, the large home of the Exposition's president, John G. Milburn.  On Saturday, September 7, they were to travel to Cleveland and stay first at the home of businessman and future Ohio governor Myron Herrick, a friend of the President, and then with McKinley's close friend and adviser, Ohio Senator Mark Hanna. Upon arrival in Buffalo, the presidential party was driven through the fairgrounds on the way to the Milburn House, pausing for a moment at the Triumphal Bridge at the Exposition so the visitors could look upon the fair's attractions.While in Buffalo, McKinley had two days of events:  On Thursday, September 5, he was to deliver his address and then tour the fair.  The following day, he was to visit Niagara Falls, and, on his return to Buffalo, meet the public at the Temple of Music on the Exposition grounds. Part of the reason for bringing McKinley repeatedly to the fair was to swell the gate receipts; the popular President's visit was heavily advertised. The public reception at the Temple of Music was disliked by his personal secretary, George B. Cortelyou, who, concerned for the President's security, twice tried to remove it from the program. McKinley restored it every time; he wished to support the fair (he agreed with its theme of hemispheric cooperation), enjoyed meeting people, and was not afraid of potential assassins. When Cortelyou asked McKinley a final time to remove the event from the schedule, the President responded, "Why should I?  No one would wish to hurt me." Cortelyou warned McKinley that many would be disappointed since the President would not have time to shake hands with all who would line up to meet him. McKinley responded, "Well, they'll know I tried, anyhow." Unable to persuade the President to...

Question: When did McKinley's trip begin?
September 4, 1901