Tachen is sometimes spelled as Dachen. http://en.wikipedia.org/wiki/Dachen_Islands Yes, I speak Mandarin.
guys, you spamming again.. oh well, i think i know where Dachen is.. never been there, i actually called my daddy to find out where is it. okay, basically my daddy said, it's right below zhoushan island, where theres alot of alot alot of fish to eat. and you guys can understand ningbo dialogue. my daddy said most Dachen people went to Taiwan..
My favourite cities are Copenhagen, Stockholm, NYC, Sydney, Ayia Napa and ofc my homecity Gothenburg(Sweden)... London is pretty cool aswell! Cheers!