Taxi, whizz along the motorway at breakneck speed and pay in excess of €50 for the pleasure. Or hire a car, if you don´t want to hire for the duration of your stay how about this for an idea.
You can hire a car from Cicar for €25 for a Corsa, picked up at TFS, dropped off 24 hours later at Puerto Santiago office (they call it their "Los Gigantes" office). The insurance is fully inclusive, except for lost keys and wrong fuel. Child seats are f.o.c. No deposit taken apart from for the fuel in the car at pick-up. This is refunded provided the car is returned with the same amount of fuel. (5 euros easily covers this).
Sounds a bargain and even doing the same on the return journey works out to the price of a one way taxi.