<human>:  I have a question about the Exxon Valdez oil spill. Where did the oil spill?
<bot>: The Exxon Valdez oil spill happened in Prince William Sound, Alaska. The oil spill was caused by a tanker ship called the Exxon Valdez, which was carrying oil from Alaska to California. The ship ran aground on Bligh Reef in Prince William Sound, spilling over 11 million gallons of oil into the ocean.