MPC is the nation's second-largest refiner, with a crude oil refining capacity of approximately 1.9 million barrels per calendar day in its six-refinery system. Marathon brand gasoline is sold through approximately 5,600 independently owned retail outlets across 20 states and the District of Columbia. In addition, Speedway LLC, an MPC subsidiary, owns and operates the nation's second-largest convenience store chain, with approximately 2,740 convenience stores in 21 states. Through subsidiaries, MPC owns the general partner of MPLX LP, a midstream master limited partnership. Primarily through MPLX, MPC owns, leases or has ownership interests in approximately 10,800 miles of crude oil and light product pipelines. Also through MPLX, MPC has ownership interests in gathering and processing facilities with approximately 5.9 billion cubic feet per day of gathering capacity, 8.4 billion cubic feet per day of natural gas processing capacity and 610,000 barrels per day of fractionation capacity. MPC's fully integrated system provides operational flexibility to move crude oil, NGLs, feedstocks and petroleum-related products efficiently through the company's distribution network and midstream service businesses in the Midwest, Northeast, East Coast, Southeast and Gulf Coast regions.
MPC refines crude oil and other feedstocks at its six refineries in the Gulf Coast and Midwest regions of the U.S., purchases refined products and ethanol for resale, and distributes refined products through various means, including pipeline and marine transportation, terminals and storage services provided by our Midstream segment. MPC sells refined products to wholesale marketing customers domestically and internationally, buyers on the spot market, our Speedway business segment and to independent entrepreneurs who operate Marathon retail outlets.
MPC’s Midstream segment includes the operations of MPLX and other related operations. The Midstream segment gathers, processes and transports natural gas; gathers, transports, fractionates, stores and markets NGLs; and transports and stores crude oil and refined products via pipelines, terminals, towboats and barges.
Primarily through MPLX, MPC owns, leases or has ownership interests in approximately 10,800 miles of crude oil and products pipelines, MPC also has partial ownership interests in several crude oil and products pipeline systems and product companies.
MPC has indirect ownership interests in two ocean vessel joint ventures with Crowley through our investment in Crowley Coastal Partners. These joint ventures operate and charter four Jones Act product tankers, most of which are leased to MPC, and own and operate three 750 Series articulated tug barge vessels that are leased to MPC.
Headquartered in Enon, Ohio, Speedway is the second-largest chain of company-owned and -operated gasoline and convenience stores in the U.S. Speedway has approximately 2,740 convenience stores in 21 states that offer a wide variety of merchandise, including prepared foods, beverages and non-food items. During 2017, Speedway sold approximately 5.8 billion gallons of transportation fuels and an additional $4.9 billion in merchandise.
Speedway pledges to be “The Customer’s First Choice for Value and Convenience.” Speedway’s marketing strategy and execution have resulted in significant success in the marketplace. Speedy Rewards?, a highly successful customer loyalty program, averaged approximately 6 million active members in 2017, and continues to grow as it attracts new members in the markets it serves.
Speedway owns a 29 percent interest in Pilot Flying J Southeast LLC, which is a joint venture between Speedway and Pilot with 124 travel center locations, primarily in the Southeast. Speedway also owns 109 transport trucks and 103 trailers for the movement of gasoline and distillate.