Going north from Palm Beach, Broward or Miami-Dad:

Take I-95 to the northern most exit in Martin County, Martin Highway / SR-714, Exit 110. 

Go West approximately 15 miles. 

At about 14 miles  you will cross a RR track.  

In 1 more mile watch the right hand side for a ranch gate. 

To the left of the gate is a sign that says DEMPSEY. 

Turn right into Dempsey. Open and close the gate.

Traveling south on I-95, take exit 110 and follow the above directions.

The coordinates for Dempsey are:

                                   27°09'43.9"N 80°38'46.4"W