As you look at the Rio map, you will see a little hump at the very top (drive like you are going to go jump off the boat). Right in the middle of the hump looking North you will see a building (there is only one building). To know you are in the right place, there is a fence on either side. On the West (left as you face North) of the building is a fence that has two white links, and then turns to black. The first white link part of the fence is the gate. As you look North at the building, the switch is to the right. If you reach the fence on the right, you have gone too far.