How long were Almanzo and Laura Ingalls Wilder married for?

Laura Ingalls and Almanzo Wilder were married for 64 years, until his death on October 23rd, 1949. They were married in De Smet South Dakota on August 25th, 1885 by the Reverend Brown.  Theirs was an exceptionally long marriage for the era, as both Laura and Almanzo lived to remarkably old age.