Which city does the ticket destination xnn represent?

XNN stands for Xining, Caojiabao Airport?

Knowledge expansion:

City code city code city code

Anqing AQG jiuzhai JZH Urumqi URC

Ankang is also known as Kunming KMG WUHan Wuh.

BAV Kashi KHG Wuyishan WUS

Beihai BHY Lanzhou LHW Wuzhou WUZ

Baoshan BSD Lianyungang LYG Xuzhou Xuz

Changde CGD Luoyang LYA Xi SIA

Changzhou CZX Lhasa LXA Xining XNN

Changchun CGQ Liuzhou LZH Xilinhot XIL

Changsha CSX Linyi LYI Xiamen XMN

Chengdu CTU Lijiang LJG Xiangfan XFN

Chongqing CKG Luzhou LZO Xishuangbanna JHG

YBP Yibin Mudanjiang Millennium Development Goals

Dandong DDC Meixian MXZ ynt Yantai

Dali DLU Nanchang KHN Yanji YXJ

Nanjing NKG Yichang YIH

Enshi ENY Nanning NNG Yiwu Yiw

Fuzhou FOC Nantong NTG Yinchuan company

Guangzhou can Ningbo NGB Yan' an ENY

Guilin KWL Qiqihar NDG Yulin UYN

Guizhou KWE Qingdao Tao Yi Ning Yin

Zhanjiang Gate, Quzhou District, Ganzhou City

Harbin HRB Qinhuangdao SHP Zhengzhou CGO

Haikou HAK sanya SYX Zhoushan HSN

Hailar Airport Shantou Airport Zhuhai Airport

Hangzhou HGH Shanghai Shamianyang MiG

Hefei HFE Shenzhen Shenzhen Dunhuang DNH

DYG Zhangjiajie Hohhot

Huangshan TXN Shao Tong ZAT

Huangyan HYN Shashi High School

Hanzhong HZG Shijiazhuang SJW

Heihe HEK Taiyuan TYN

Jilin JIL Tongliao TGO

Jinan TNA Tianjin TSN

Jiamusi JMU Tasca TAS

JJN Weihai WEH Jinjiang

Jingdezhen JDZ Weifang WEF

JGN Jiayuguan Wenzhou WNZ

Jinzhou JNZ ulanhot HLH