The Marland Estate (Marland Mansion) is in Ponca City, Oklahoma — not "Poca City." This 43,561 sq ft, 55-room Italian Renaissance villa was built 1925-1928 for oil baron E.W. Marland (later Oklahoma governor, 1935-1939).
City-owned since 1941 (tax default). National Historic Landmark (1977). Operated as historic house museum. Tours: Tuesday-Saturday 10-5, Sunday 1-5. Admission: $12 adults. Events: Christmas tours, oil history symposium, wedding venue.
Marland's Grand Home (1914-1916, first Marland mansion, now Ponca City Cultural Center). Conoco Museum (Marland Oil → Continental → ConocoPhillips). Standing Bear Park (Ponca Tribe).
Search "Marland Mansion Ponca City" — GPS: 36.707°N, 97.083°W.