what is the speed limit on i 90 in south dakota
Since April 2015 the speed limit is 80 miles per hour (130 km / h), except it is 65 miles per hour (105 km / h) between I-229 and Marion Road in Sioux Falls; or through Rapid City. The speed limit remains 75 miles per hour (121 km / h) between Rapid City and the Wyoming state line.