US Defence Secretary Robert Gates on Wednesday visited China's nuclear warfare headquarters, at the end of a four-day visit to China. Mr. Gates got a rare look at the Second Artillery Corps headquarters outside Beijing, which oversees nuclear and missile forces. The Pentagon chief said he had very candid conversations during his tour of the facility in Qinghe and spoke to Chinese officers about nuclear strategy. Both the US and China have long-range missiles capable of reaching each other's shores, but both have said they do not intend to use them. Officials from both countries praised Mr. Gates' visit as a success which comes ahead of a trip by Chinese President Hu Jintao to Washington next week. Mr. Gates leaves for Tokyo on Wednesday and then Seoul on Friday, for meetings focused on North Korea.