On June 18, 1971, Southwest Airlines began intrastate operations in Texas. The “Love Bird” service out of Dallas Love Field offered twelve daily round-trip flights from Dallas to Houston and six round-trip flights from Dallas to San Antonio on Boeing 737-200s. Since starting service, Southwest has the distinction of almost exclusively operating the Boeing 737 family, except for a brief period when the airline operated Boeing 727s. The airline inaugurated service to SFO in 1982.