Question: What is the oldest section from where Robert Hay was born?

Context articles: Thomas Bull House
Robert Hay (Egyptologist)
Oak Grove (Altavista, Virginia)
Peter Spicker House
Lafayette's Quarters
Gen. John Lacey Homestead
Duns Castle
James Stewart House (Glasgow, Delaware)
Martin-Little House
Windsor Forge Mansion

Thomas Bull House, also known as Robert's Plantation, Redding Plantation, and Mt. Pleasant, is a historic home located in East Nantmeal Township, Chester County, Pennsylvania.
 The house is in three parts.
 The oldest section was built about 1715.
 It is part of the two-story, four bay eastern section of the stone dwelling.
 The two-story, three bay, third section was probably built between 1783 and 1796.
 The interior of the older part features a circular staircase that wraps around the chimney.
 It is an example of late Georgian / early Federal architecture.
Robert Hay (6 January 1799 – 4 November 1863) was a Scottish traveller, antiquarian, and early Egyptologist.
 He was born in Duns Castle, Berwickshire.
 During his service in the Royal Navy he visited Alexandria, Egypt, in 1818.
Oak Grove is a historic plantation house located near Altavista, Campbell County, Virginia.
 It was built in stages between the 1750s and 1833.
 The oldest section is a two-story dog-trot log structure built around 1750.
 The house was enlarged in 1784, and completed around 1833 by adding a west wing.
 It is a two-story, three bay structure containing a large hall and a parlor on the first floor and a stair hall and two bedrooms on the second in the Federal style.
 Also on the property are a contributing smokehouse, a slave quarter, a grain shed, a hay barn, and a privy as well as the remains of a kitchen and an icehouse.
Peter Spicker House is a historic home located at Stouchsburg, Marion Township, Berks County, Pennsylvania.
 It is a native limestone dwelling with first section was built about 1740, with the central portion added about 1750, and the eastern section about 1800.
 It is reflective of the transition from the Germanic to the Georgian style.
 The oldest section is 1 1/2 stories, three bays wide.
 The central section is 2 1/2 stories and also three bays wide, with a gable and pent roof.
 The eastern section is also 2 1/2 stories, six bays wide, with a gable roof.
 Also on the property is a late-18th century, stone Pennsylvania German bank barn.
Lafayette's Quarters, also known as the Brookside Inn, is a historic home located on Wilson Road south-southeast of the intersection of Yellow Springs Road and Wilson Road in Tredyffrin Township, Chester County, Pennsylvania.
 This house is not opened to the public.
 The house was built in three sections, with the oldest dated to 1763.
 The center structure is dated to about 1837-1839, and the western section was added between 1882 and 1900.
 The oldest section is a 2 1/2-story, two bay by three bay, stuccoed stone structure with a gambrel roof.
 The center section is of stuccoed stone, three bays long and two bays wide.
 The western section is a frame structure.
 It was renovated in 1948.
 During the American Revolution the house served as headquarters for Major General Gilbert du Motier, marquis de Lafayette in late-1777 and early-1778, during the encampment at Valley Forge.
Gen. John Lacey Homestead is a historic home located at Wycombe, Buckingham Township, Bucks County, Pennsylvania.
 It was built in six sections over 200 years, with the earliest constructed in 1755.
 The oldest section is a 2 ⁄ -story, random-fieldstone structure with a slate-covered gable roof.
 Attached to it are two 2 ⁄ -story, fieldstone sections with slate gable roofs.
 The fourth section is a 1 ⁄ -story, plaster-covered stone section.
 The fifth section is a 1 ⁄ -story, enclosed porch with a shed roof.
 The sixth section is a 1 ⁄ -story, frame section with a gable roof.
 It was the home of Revolutionary War General John Lacey (1755–1814).
Duns Castle, Duns, Berwickshire is a historic house in Scotland, the oldest part of which, the massive Norman Keep or Pele Tower, dates from 1320.
James Stewart House, also known as Holly Farm, is a historic home and farm located near Glasgow, New Castle County, Delaware, United States.
 The oldest section dates to the second half of the 18th century, with additions dating to the 18th and 19th centuries.
 It consists of three distinct two-story, gable-roofed, brick sections joined at the endwalls, plus a one-story, brick lean-to.
 The oldest section is the first floor of the central section.
 Also on the property are contributing outbuildings including a brick smokehouse, shop, a corn crib/granary, two sheds, a privy, a bank barn, a milkhouse, and a machine shed.
Martin-Little House is a historic home located in Charlestown Township, Chester County, Pennsylvania.
 It consists of five sections built between about 1735 and 1960.
 The oldest section was built about 1735, and is a 1 1/2-story, stuccoed stone saltbox form dwelling.
 A 2 1/2-story, five bay, stone main section was added as a wing in 1810.
 Later additions are the two-story kitchen wing dated to the late-19th century; two-story bedroom wing from the mid-20th century; and one-story, shed roofed frame addition of 1960.
 The oldest section may have served as a stagecoach stop and post office in the mid-18th century.
Windsor Forge Mansion, also known as Windsor Place, is a historic home and national historic district located at Caernarvon Township, Lancaster County, Pennsylvania.
 The district includes four contributing buildings and three contributing objects.
 The buildings are the Ironmaster's Mansion, stone smokehouse (c. 1765), stone spring house (c. 1765), and stone summer kitchen / servant's quarters (c. 1765).
 The three objects are pieces by noted artist and poet Blanche Nevin (1841-1925), who purchased Windsor Forge Mansion in 1899.
 Her grandfather Robert Jenkins (1769 - 1848) had previously been ironmaster and congressman.
 The oldest section of the Ironmaster's Mansion was built about 1742; the western section was built about 1765, and the connecting middle section about 1815.
 A shed roof porch was added in 1899, at which time it was generally renovated.
 The house is 2 1/2-stories and built of stone.
 Nevin added a studio to the house.