These files include the acoustic data acquired from Posidonia oceanica meadows for the study entitled "Vertical configuration of a Side Scan Sonar for the monitoring of Posidonia oceanica meadows". The acoustic height of the canopy and the accumulated intensity for each surveyed site have been calculated from these data. The acoustic data are presented as follows: - In the case of Dénia measurements, the filenames correspond to the sites. D_1 includes only meadow part, not the bare seabed. - In the case of Calp measurements, the filenames correspond to sites followed by the number of repetition. - Every file contents the following: (1) echogram -> Intensity echograma (in dB re Pa) after applying the compensation of the geometrical spreading and attenuation losses. Columns are the pings. Rows are the samples in time, every one equivalent to 0.0122 m. (2) GPS -> latitude and longitude data for each ping, (EPSG:4326-WGS84).