Hengqin

Hengqin is an island in Zhuhai that is adjacent to Macau.  It is 3 times the size of Macau but only has a population of 3,000.  It seems like a no-brainer to expand Macau onto Hengqin.  Already, the University of Macau is building a new campus there.  It will be connected to Macau via an under-river tunnel.

It sounds to me like it is pronounced "Hong Cheng".