[6] Dallas is along Rickreall Creek, about 15 miles (24 km) west of Salem, at an elevation of 325 feet (99 m) above sea level.

According to the county historical society in 1987, Mrs. Thomas J. Lovelady named the new settlement after her home town of Cynthiana, Kentucky.

[9] Another source claims that Cynthia Ann, wife of early pioneer Jesse Applegate, named the settlement.

Its residents raised $17,000 in order to have a branch of the narrow gauge railroad constructed to their town, which secured them the honor and related economic stimulus.

[7] Town leaders believed a more sturdy sounding name was needed for a county seat.

[citation needed] After Louis Gerlinger, Sr. incorporated the Salem, Falls City and Western Railway Company late in October 1901, he announced plans to build a railroad from the Willamette River at Salem to the mouth of the Siletz River on the Oregon Coast, a distance of 65 miles (105 km).

[10] In 1902, Louis's son George T. Gerlinger organized a group of investors to build related railroad lines in the area.

According to the United States Census Bureau, the city has a total area of 4.81 square miles (12.46 km2), all of it land.

Occasionally frigid weather will reach the Willamette Valley due to very cold continental air from Canada being driven over the Cascades by a low-pressure system to the south, as occurred repeatedly in January 1950 when temperatures reached as low as −11 °F (−23.9 °C) on January 31, 1950, and 68.0 inches (173 cm) of snow fell.

Spring arrives slowly with pleasant afternoon temperatures and less heavy rainfall by April, although showers are common until into June.

Low humidity and pleasant mornings make this season comfortable, although airflows from the hot continent can bring spells of sweltering and arid weather, with 106 °F (41.1 °C) reached on July 19, 1956, and on August 8, 1981.

On average, eighteen afternoons will top 90 °F (32.2 °C) but only two can expect to reach 100 °F (37.8 °C), while 62 mornings fall below freezing, but only two spells (in January–February 1950 and December 1972) have ever seen temperatures as low as 0 °F (−17.8 °C).