 The city 's sandy fresh water beaches are a popular tourist attraction , while the sheltered harbour houses marinas for recreational sailing . Since 1925 , the 400 km ( 250 mi ) Mackinac race from Sarnia / Port Huron to Mackinac Island at the north end of the lake has been the highlight of the sailing season , drawing more than 3 @,@ 000 sailors each year . 
 The city <a href='null_genetive' title='1'><mark>'s</mark></a>sandy fresh water beaches <a href='drop_aux' title='2'><mark>are</mark></a>a popular tourist attraction , while the sheltered harbour houses marinas for recreational sailing . Since 1925 , the 400 km ( 250 mi ) Mackinac race from Sarnia / Port Huron to Mackinac Island at the north end of the lake <a href='uninflect' title='3'><mark>has</mark></a> been the highlight of the sailing season , drawing more than 3 @,@ 000 sailors each year . 
Da city  sandy fresh water beaches a popular tourist attraction , while the sheltered harbour houses marinas fa recreational sailing . Since 1925 , tda400 km ( 250 mi ) Mackinac race from Sarnia / Port Huron to Mackinac Island at the north end of the lake have been thdaighlight of thedailing season , drawing more den 3 @,@ 000 sailors each year .