Oops, it doesn't look like 'park entrance park entrance day' is a national day..

Other days

buddy

Buddy Day

first love

First Love Day

eat what you want

Eat What You Want Day

ask out your crush

Ask Out Your Crush Day

self care

Self Care Day

lost sock memorial

Lost Sock Memorial Day

blanket fort

Blanket Fort Day

slime

Slime Day

ruby

Ruby Day

chocolate milkshake

Chocolate Milkshake Day