This beach is the most important of San Andrés, and is in addition, the most visited by the tourists and residents. In previous decades the beach did not look as it does nowadays. In the 1950s there only existed the layout of the present highway (that is to say without pavement) and the beach areas contained important amounts of vegetation (grass and coconut palms); also, the beach was divided in three zones, first between Hotel Aquarium and Lord Pierre, second between the Antiochian boardinghouse and Abacoa Hotel, and the third between the Tiuna Hotel and civil defense; in some sites the outcrop of rocky beds was evident. The adjacent beaches at the pescadero were under continuous attack of currents and surge, which were causing serious erosive processes. During the 1980s the concrete outfalls and the Tiuna Hotel were constructed, and also a retaining wall was constructed in front of the track. The construction of these works substantially modified the dynamics of beaches and generated a sediment accumulation that resulted in the beach as we know it nowadays.

The great influence of tourists and users of the beach, as well as the construction of the highway behind the beach, produced a diminution of the existing vegetation, the grass beds were lost, as well as a great amount of coconut palms. The dynamics of the beach transfers coral sand between the outfalls that were constructed, this situation leads to that at certain times of the year serious erosive phenomena in some zones and processes of sedimentation of others appear. At other times, strong winds and the lack of vegetal cover, have resulted in the loss of sand. Nevertheless, in the 1980s a stone wall was constructed to separate the walk and the beach, that goes from the Civil defense to the Antiochian boardinghouse; this contributed to the loss of the small dunes created by wind drifts.

For these reasons CORALINA has being working with the different institutions like CEMED, Luis Amigo, Industrial, Cajasai, Sagrada Familia, and Natania, to monitor the beach using two poles 2 m high measured in centimeters, a piece of rope and a level. In the process we have observed that the sand level changes during November and December because of the weather conditions (rainy season) in these months.

The students are very interested to continue working with these methods because they are easy to manage and they can see the different changes that the beach made during the process of measurements.