Chinese authorities require that travelers have valid visas to exit China and to travel and register in hotels within China. Useful information on guarding valuables and protecting personal security while traveling abroad is provided in the Department of State pamphlet, A Safe Trip Abroad. Passports and visas are required. Conference and NGO Forum participants require a business visa. The length of stay is determined by the amount of time requested when applying for the visa.
Most tourist visas are valid for only one entry.
Travelers require a new visa for additional entries into China. U.S. consular officers are not always notified when a U.S. citizen has been detained. However, U.S. citizens have rights to consular access under the U.S. - P.R.C. Consular Convention and should insist upon contact with the U.S. Embassy or one of the U.S. Consulates General. If you are denied this right, continue to protest. Under the U.S. -P.R.C. Consular Convention of 1980, U.S. consular officers shall be notified if a U.S. citizen is arrested or detained no later than four days after the arrest or detention.