Shortly after the Mormon pioneers arrived, Brigham Young directed that the streets in downtown Salt Lake City be wide enough for a wagon team to turn around without "resorting to profanity."

Over the years, those streets have maintained their 132-foot width. But a lot has changed.

Many of the Main Street changes have been documented by Deseret News photographers and illustrators. Photo researcher Ron Fox has found many of these photos in the newspaper's archives, beginning with an illustration from the early 1860s of the single-story Deseret News offices located, as they are now, on 100 South between Main and State streets.

The city's famous grid system actually dates back to Joseph Smith, founder of The Church of Jesus Christ of Latter-day Saints, who imagined a template for the "City of Zion" that might be applied to Mormon towns everywhere.

Starting from scratch in Salt Lake Valley, Young was able to realize Smith's plan to a degree. Although the geography of the Avenues area defied the plan, downtown Salt Lake City still bears the stamp of that vision.

The photos, many taken near 100 South and Main Street from the 1860s to 1953, show the progress of Salt Lake from an isolated territorial outpost to a modern city. They also chart the progress of transportation from the initial days of the horse and buggy, to the mule-drawn streetcar system of the 1870s and to the Salt Lake Rapid Transit Company's electric railway installed in 1889.

By that time, Salt Lake City's downtown streets were a maze of rail lines and utility poles, many of which ran down the middle of the street.

In those days, Salt Lake City's unpaved streets were rated among the dirtiest and unhealthiest in the West, a situation that prompted years of beautification efforts, including the laying of five miles of sewer pipe under the streets.

But the city was always looking ahead. In a 1905 edition of Deseret News, a cartoonist took a peek into the future and came up with a fantastic view of downtown Salt Lake City as it would appear 10 years later.

An illustration published in the newspaper shows a Salt Lake City in 1915 with tall buildings on either side of the street, run-away automobiles chasing pedestrians with no regard to lanes or rules of traffic, and dirigibles carrying passengers through the sky.

Photos published in the 1912 Deseret News, however, show no dirigibles and pedestrians are crossing the street with no threat from automobiles. Tall buildings line both sides of the street, however, much as they do today.

A 1930 photo of a multi-story Deseret News building shows a trolley running along rails down the middle of the street. At the time, trolleys were being phased out in favor of gas-powered buses, and a 1949 photo shows a Main Street free of rail lines and diagonally parked cars lining the street.

Main Street 2009 resembles the 1930 photo more than it does the 1949 picture, an indication that change is not always permanent.

And despite Brigham Young's best intentions, traffic on Salt Lake City's downtown streets continue to inspire its share of profanity.