From September 30, 1777 to June 27, 1778, York, Pennsylvania, Court House hosted the Second Continental Congress, thus serving as our capital for those nine months.

Second Continental Congress locations:

May 10, 1775 to December 12, 1776: Philadelphia, State House

December 20, 1776 to February 27, 1777: Baltimore, Henry Fite’s House

March 4, 1777 to September 18, 1777: Philadelphia, State House

September 27, 1777 (one day): Lancaster, Pennsylvania, Court House

September 30, 1777 to June 27, 1778: York, Pennsylvania, Court House

July 2, 1778 to March 1, 1781: Philadelphia, College Hall, then State House

Source: Robert Fortenbaugh, The Nine Capitals of the United States, page 9.

http://www.senate.gov/reference/reference_item/Nine_Capitals_of_the_United_States.htm

More Info: en.wikipedia.org