wichita is the biggest city in kansas; it has almost 400,000 people. it is in sedgwick county, which has about 520,000 people. sedgwick county has the biggest city in kansas, but it does not have the most people of any county in kansas; johnson county has more than 600,000 people. johnson county has four of the biggest cities in kansas: overland park, olathe, shawnee, and lenexa. they are all suburbs of nearby kansas city. topeka is the capital of kansas. lawrence is a college town between kansas city and topeka.