South of Dover near Seaford, the Speed Citi Motorsports (aka Middleford Speedway or Delmarva Motorsports Park) has a motocross and a flattrack.
To reach the dirt biking at the speedway, head south on SR13 to SR404/18. Head east on SR404/18 for 5 miles to blinking light. Turn right on CR525 for 4 miles to the large dirt hill on the right. The track entrance is between the trees on the right. The motocross track is located at 22112 Coverdale Road in Seaford.
Overall, Speed Citi Motorsports is the 2nd most popular dirt bike trail of all 2 dirt biking rides in Delaware.