There are 4 ways to say "to the" because there are 4 ways to say "THE":
"THE" = el, la, los, las
"EL, LA , LOS, LAS" are chosen by looking at the ending of the noun.
BANCO - ends in "o" CHOOSE: "EL"
PISCINA - ends in "a" CHOOSE: "La"
MERCADOS - ends in "OS" CHOOSE: "LOS"
PLAYAS - ends in "AS" CHOOSE "LAS"
*Some words do not end in "o, a, os, as" & YOU just have to memorize which form of 'THE" to use
There is only 1 way to say "TO" & that is the word "a"
SO, the 4 ways to say "to the" are:
al (which comes from combining "a + el"
a la
a los
a las
"to the mountains"
"to the beaches"
"to the store"
"to the LAKE"
"to the market"
"to the STORES"
"to the PHARMACY"
"to the stadiums"
"to the restaurante"
"to the lakes"
"to the STORE"