Fort Pitt Blockhouse The Fort Pitt Block House ( sometimes called Bouquet ' s Blockhouse or Bouquet ' s Redoubt ) is a historic building in Point State Park in the city of Pittsburgh . It was constructed in 1764 as a redoubt of Fort Pitt , making it the oldest extant structure in Western Pennsylvania , as well as the " oldest authenticated structure west of the Allegheny Mountains " . Construction . The Block House was constructed in 1764 as a defensive military redoubt . Henry Bouquet initiated the construction of a small number of redoubts around the outer walls of the fort as a way to reinforce its defense , of which only the Fort Pitt Block House survives . History . When Fort Pitt was demolished in 1792 , the Block House was left untouched because it was already in use as a residence . The structure was converted into a private house in 1785 by Isaac Craig . In 1894 , philanthropist Mary Schenley presented the deed to the Block House to the Daughters of the American Revolution ( DAR ) . She did this specifically so that the structure might be preserved for future generations : You are to preserve and keep this relic of a bygone past , and to gather and preserve all obtainable history and tradition in regard to it , and you are to beautify and adorn it and to make it the receptacle of relics bearing on the Colonial and Revolutionary periods of its existence . … I will therefore … leave the ladies of your Society , who have the history of western Pennsylvania at their finger ends , to tell the story of the chivalrous Frenchmen , cruel , crafty Indians , courageous British , and intrepid Colonists . It is fitting that this old landmark , rich in historic associations of more than a century ago , should fall into the hands of those who by birth , tradition , and sentiment are particularly fitted to receive and preserve it and perpetuate the memories of the days when it was occupied by the French and their Indian allies , and afterwards by the British and Colonial troops . Industrialist Henry Clay Frick purchased all of the land surrounding the Block House in 1902 , shortly before Schenley ' s death . He offered the DAR $ 25 , 000 to move the Block House to Schenley Park ; however , the DAR refused . Following lengthy litigation , the Supreme Court of Pennsylvania ruled in favor of the DAR and the Block House , enabling its continued preservation . The structure has never been torn down , completely rebuilt , or moved during its centuries of existence . Much of its timbers , brick , and stone remain original to its 1764 construction . Today . Although the Block House resides within the boundaries of Point State Park , it is owned and operated by the Fort Pitt Society of the Daughters of the American Revolution . The DAR allows visitors to the park to tour the structure . The building is recognized by the National Register of Historic Places as being the sole surviving historical building in the " Forks of the Ohio ( Site of Fort Duquesne and Fort Pitt , Bouquet ' s Blockhouse ) " historic place . It also has a historical marker issued by the commonwealth of Pennsylvania and is a Pittsburgh History & Landmarks Foundation designated Historic Landmark .