1860 January 0
Allegheny Observatory was founded.

1860 January 0
Population: 49,221; Allegheny City, 28,702; Allegheny County, 178,031.

1860 June 22
An announcement was made of the opening of "books to receive subscription of stock" for construction of a "free bridge" over the Allegheny.

1860 July 29
Professor S. Wilson ascended from Pittsburgh in his balloon, great Western, disappeared from view, and landed hours later on a bill near Sharpsburg.

1860 October 1
The Prince of Wales, the later Edward VII of the United Kingdom, was warmly greeted by Pittsburghers when he arrived at the Monongahela House for an overnight stay. He visited factories and manufacturing establishments.

1860 November 28
Because of Civil War clouds, all Pittsburgh banks except the Bank of Pittsburgh suspended specie payments.

1860 December 0
The city refused to comply with the Secretary of War's order for the transfer of guns from the Allegheny Arsenal to the South.

1861 January 0
Baltimore and Ohio Railroad, via connecting railroads, was extended to the city.

1861 January 0
The Trimble Construction Company began operations as the Crawford, Trimble and Gilliland Company.

1861 February 15
From a balcony of the Monongahela House, President-elect Lincoln, who had stopped in the city on his way to Washington, in a reference to the secession from the Union of southern states, declared that "notwithstanding the trouble across the river, there is no crisis but an artificial one."

1861 April 0
Camp Wilkins, near Penn Avenue and 26th Street, was established by Governor Andrew G. Curtin; a home guard was organized.

1861 April 24
Eighty men comprising "Turners Rifles" departed for Harrisburg to join Union troops; they became the first Pittsburgh soldiers to see action in the war.

1861 August 0
Bernard Lauth retired and James Laughlin bought his interest. Jones, Lauth, and Company became Jones and Laughlin's American Iron Works.

1861 September 21
Property damage was heavy in a flood that reached a mark of 30 feet, 9? inches.

1861 October 0
United States Sanitary Commission, designed to receive donations of clothing and medical supplies for the Army, was established by the Citizens Committee of 100, which had been selected at a mass meeting in City Hall on April 15.