EDITORIAL: PIONEER DAY IS FOR ALL UTAHNS
From the earliest days of the state, this date has been set aside to remember and celebrate the pioneers, the first of the Mormon settlers who entered Salt Lake Valley in 1847. If the day fell on a Sunday, as it does this year, the formal celebrations always have been on the following Monday. Ref. Source
Pioneer celebration: This Is the Place offers lots to do over the 24th
Brigham Young and the final wagons of the first pioneer company entered the Salt Lake Valley on July 24, 1847. Because it was so late in the season and the pioneers had crops to plant and houses to build, there was little time to celebrate their arrival, although one can imagine the joy they felt in finally reaching their journey's end. Ref. Source 5
Pioneer Day (Hover)