The 1859 Pennsylvania well widely regarded as the first commercial oil well was the Drake Well.
Edwin Drake drilled the well near Titusville, Pennsylvania, for the Seneca Oil Company. It reached oil at a depth of about 69.5 feet (21.2 meters) on August 27, 1859. The operation used a steam engine and a drive pipe, techniques that helped make drilling more systematic.
Oil had been collected from natural seeps before Drake's well, but the well demonstrated that petroleum could be produced in dependable commercial quantities. Its success helped trigger rapid drilling and refining activity in western Pennsylvania and is often used as a symbolic starting point for the modern petroleum industry.
The well was not the world's first oil well in an absolute sense. Earlier wells existed in places including China and the Caucasus. Drake Well is specifically remembered for helping launch the modern commercial oil industry in the United States.