La Pared (The Wall)

A volcanic rock face on the outer Catalina Islands off Guanacaste, dropping from about 12 metres to past 24 along a single sloping wall locals call Shark Alley. Cold nutrient rich upwellings between November and April pull oceanic manta rays with wingspans over 6 metres, mobula schools of dozens to hundreds, and squadrons of cow nosed and spotted eagle rays through the cleaning stations on the ridge. White-tip reef sharks rest in the channels at the base, with schooling jacks, snapper and the occasional bull or whitetip in the blue. Strong tidal currents and a sharp thermocline make for serious diving, but it is the most reliable Pacific manta encounter in northern Costa Rica.