I-90 is THE road ringing the northern Black Hills and is very heavily patrolled. Speed traps can and are set up in numerous places to include but not limited to: near exit 2, near exit 8, exit 17 (Deadwood turn off), vicinity of mile marker 29, near exit 32, near mile marker 34-36 and the port of entry, near mile markers 46 to 48, east of exit 55, east of mile marker 60, and out to the exit for EAFB.