Question: Marin Čilić won a Masters 1000 title at the 2016 tournament held in what suburb of Cincinnati?
Related documents: [0]  [DOC] This is a list of the main career statistics of Croatian professional tennis player, Marin Čilić. To date, Čilić has won 16 ATP singles titles including one grand slam singles title at the 2014 US Open, one ATP Masters 1000 title at the 2016 Western & Southern Open and a record four titles at the PBZ Zagreb Indoors. Other highlights of Čilić's career thus far include a semi-final appearance at the 2010 Australian Open and three consecutive quarterfinals at the Wimbledon Championships from 2014 to 2016. Čilić achieved a career high singles ranking of World No. 6 on November 21st, 2016. [END] 
[1]  [DOC] The 2016 Western & Southern Open was a men's and women's tennis tournament played on outdoor hard courts from August 15–21, 2016. It was a Masters 1000 tournament on the 2016 ATP World Tour and a WTA Premier 5 tournament on the 2016 WTA Tour. The tournament was one of two headline events in the 2016 US Open Series. The 2016 tournament was the 115th men's edition and the 88th women's edition of the Cincinnati Masters. The tournament is held annually at the Lindner Family Tennis Center in Mason (a northern suburb of Cincinnati), Ohio, United States. [END] 
Answer: 
Mason
Mason