A plaque marking the base and meridian of Salt Lake City was unveiled in conjunction with MIA June Conference on Sunday, June 12, 1932, according to the previous day's edition of the Church News.
The article said the plaque would be placed on the east wall of the Salt Lake Temple. Today, it is on the southeast corner of the wall around Temple Square.
The inscription on the plaque says, in part: "Great Salt Lake Base and Meridian.
"Latitude 40 degrees, 46 minutes, 4 seconds.
"Longitude 111 degrees, 54 minutes.
"Altitude (sidewalk) 4327 feet.
"Fixed by Orson Pratt, assisted by Henry G. Sherwood, August 3, 1847, when beginning the original survey of 'Great Salt Lake City,' around the 'Mormon' Temple site designated by Brigham Young, July 28, 1847. The city streets were named and numbered from this point."
President Anthony W. Ivins, first counselor in the First Presidency, spoke at the ceremony, which was conducted by President George Albert Smith, then superintendent of the YMMIA. The plaque was unveiled by Lathilla Pratt Kimball, oldest living daughter of Orson Pratt.