Melbourne, Florida

The simplified fmulroa is d = √(12.7 h), where d is in kilometers and h is in meters. Solving for h yields h = db2/12.7. Cuba is about 800 km from Panama City, so you would have to be at least 50.3 km above Panama City Beach to see the beach in Cuba. Some of the mountains west of Havana might be seen from a lower height, though they are farther from Panama City Beach.

Florida! I was there...some quater of a century earlier...but whatever!