Complex sentence: Prior to that, Junqueira street and surroundings was already a bustling fishing quarter, but as the 19th century moved in, and beach therapy became popular with the elites, Junqueira became a shopping street.
Split into simpler sentences: Prior to that, Junqueira street and surroundings were already a bustling fishing quarter. As the 19th century moved in, and beach therapy became popular with the elites, Junqueira became a shopping street.