There's more to August than just the dog days. Celebrate all month long with a calendar full of offbeat holidays.

1. August 1: Girlfriend's Day

Forgot to plan something for this holiday you didn't know existed? It's okay—just remind her that every day is girlfriend's day so you can celebrate tomorrow.

2. August 2: National Mustard Day

Real aficionados should head to Middleton, WI where they can check out the National Mustard Museum.

3. August 3: Sisters Day

Hannah Keyser

This is Emelye Keyser, she is better than your sister.

4. August 4: Single Working Women's Day

A day to honor all women who manage to bravely get up and go to work each morning while suffering from—or relishing—singledom.

5. August 5: National Underwear Day

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Underwear emporium Freshpair founded National Underwear Day on August 5th, 2003 and since then it has grown to include events around the country. Last year, they tried to set a new Guinness World Record for largest gathering of people in their underwear. The group fell short, but 800 people gathered in Times Square in just their underwear.

6. August 8: Happiness Happens Day

Celebrated annually on the founding date of the Secret Society of Happy People, which you can join for $29.95.

7. August 9: Veep Day

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Commemorates the day in 1974 when Gerald Ford became President without ever having been elected for either Vice President or President. Ford had become Vice President after Spiro Agnew resigned due to a kickback scandal. When Nixon later resigned amid the Watergate scandal, Ford made it all the way to Commander-in-Chief.

8. August 12: Vinyl Record Day

First declared such in 2002, Vinyl Record Day is held on the anniversary of when Thomas Edison invented the phonograph in 1877.

9. August 15: Best Friends Day

You don't need an excuse to hang out with your best friend. But it can't hurt.

10. August 18: Bad Poetry Day

Sure, poetry is subjective. But some of it is just bad.

11. August 19: National Aviation Day

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In 1939, Franklin D. Roosevelt issued Presidential Proclamation 2343 making August 19, Orville Wright’s birthday, National Aviation Day.

12. August 21: Poet’s Day

A day to soothe the bruised egos of Poets mocked just three days before.

13. August 24: Anniversary of Pluto’s demotion

Okay, this one isn't really a holiday. But Pluto deserves at least one day a year of remembrance.

14. August 26: National Dog Day

...also Women’s Equality Day.

All photos courtesy of iStock unless otherwise noted.