Mexico's history goes back to ancient times. The earliest known civilization in the Central Mexico and Gulf region is the Olmecs (1400-400BC), whose giant stone heads can be seen in museums in Mexico City and Jalapa and the open-air sculpture park in Villa Hermosa. The people who built the great pyramids at Teotihuacan (1st millennium AD) are something of a mystery, although the subsequent civilisations (Toltec and Aztec notably) all owe something to them. The Aztecs are relative newcomers and didn't found their capital city, Tenochtitlan, until the early 14th century AD. Just over 200 years later (1521) they were conquered by the Spaniards and so began the colonial period. It wasn't until 1810 that Mexican rebels began their fight for Mexico's independence under the leadership of a parish priest, Miguel Hidalgo. The next 100 years were turbulent, with the newly independent state losing large tracts of territory to the US and constant wars and upheavals until a period of stable but stifling dictatorship known as the Porfiratio that lasted until the Mexican Revolution of 1910. Stability did not return immediately, but then the country was ruled by one party (the PRI) until the elections of 2000. Mexico is now a thriving if chaotic democracy that will celebrate both the 200th anniversary of Independence and the 100th of the Revolution in 2010.