US Highway 24 and Kansas Highways 18 and 177 provide excellent access from nearly every direction. 

From East I-70
Exit I-70 at the Manhattan exit number 313. 
Go north on K-177 for about 9 miles.
Once over the Kansas River exit the off ramp at Tuttle Creek Boulevard.   Turn left at the light at the end of the ramp.  Manhattan Town Center will have two entrances to your immediate left.  

From West I-70
Exit I-70 at interstate exit 303 and proceed 6 miles east on K-18. Once in Manhattan, follow K-18/Ft. Riley Blvd. east to Tuttle Creek Blvd. Turn left at the light at the end of the ramp.  Manhattan Town Center will have two entrances to your immediate left.