You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
2008_Sichuan_earthquake

Context:
On May 12, 2009, China marked the first anniversary of the quake with a moment of silence as people across the nation remembered the dead. The government also opened access to the sealed ruins of the Beichuan county seat for three days, after which it will be frozen in time as a state earthquake relic museum, to remind people of the terrible disaster. There were also several concerts across the country to raise money for the survivors of the quake.

Question:
How long was it opened for?

three days