Late 1950s: BP starts to investigate potential fields in Alaska’s North Slope, initially with little success.
1963-64: BP’s geologists report positive findings in the Colville River area and Prudhoe Bay. BP initially acquires 318,000 acres in the Colville area and months later. when the Alaskan state puts land at Prudhoe Bay up for sale, BP acquires 90,000 acres.
1966-67: Alaska offers up more Prudhoe Bay leases, and after little oil is found in the Colville area BP acquires more land in the Prudhoe Bay area.
1968: After several failures on the North Slope BP considers abandoning the area. However, Atlantic Richfield (Arco) – later acquired by BP – discovers oil in one of its wells in Prudhoe Bay. Buoyed by Arco’s success, BP continues drilling and in March 1969 its Put River No.1 well strikes oil. The discoveries prove to be the biggest oilfield in North America.
1977: First oil produced from Prudhoe Bay. After years of debate over the environmental impact and opposition from Native American tribes, the Trans-Alaska Pipeline System, an 800-mile pipeline from Prudhoe Bay to Valdez, near Anchorage, begins to transport crude.
1989: Tanker Exxon Valdez runs aground, spilling 11m gallons of oil across Alaska’s Prince William Sound.
2001: A crude oil spill at the BP-operated Prudhoe Bay field comes ahead of a controversial vote in Washington to open up Alaska’s Arctic National Wildlife Refuge (ANWR) – the last potential major field left in North America – to oil drilling.
2002: One of BP’s Prudhoe Bay wells explodes, seriously injuring a worker and causing a spill. Following the explosion, BP withdraws from a group trying to open the ANWR to oil drilling.
2003: Senate efforts to open ANWR for oil drilling are blocked.
March 2006: A pipeline at Prudhoe Bay spills up to 270,000 gallons of crude.
July: BP shuts 12 Alaskan wells.
August: BP shuts its Prudhoe Bay after tests find “severe corrosion” in a pipeline.