August 23 is the 235th day of the year (236th in leap years), with 130 days remaining until the end of the year.

National Days on August 23rd
August 23 National Days

The date honors the abolition of the slave trade, celebrates innovations like the World Wide Webhashtags, and human-powered flight, while also giving space to quirky and heartfelt observances such as blind dog awareness and nerdy passions. Sweet and savory traditions are also recognized through sponge cake and the Cuban sandwich.

Here’s a look at the 10 national and international days celebrated on August 23.


National and International Days on August 23

Cheap Flight Day is an unofficial observance tied to the end of the summer travel season, when demand drops as students return to school and families travel less. First popularized around 2015 by travel platforms such as CheapOair, the date highlights a period when airlines often reduce fares to fill seats. While not a guarantee of the lowest prices, it reflects a seasonal trend in air travel and serves as a reminder of the dynamics between demand and pricing.

Find Your Inner Nerd Day was created in 2022 by author and speaker Beth Ziesenis, known as “Your Nerdy Best Friend,” to encourage people to celebrate their quirks and passions. Timed to coincide with the anniversary of the first hashtag on Twitter, the day inspires people to share hobbies, collections, or interests they might usually keep private, fostering pride in individuality and connection through shared enthusiasm.

Health Unit Coordinators Day was established in 1984 by the National Association of Health Unit Coordinators (NAHUC) to honor the profession’s contributions to healthcare. The role emerged after World War II, when hospitals faced staffing shortages and clerical support was needed to assist nurses and doctors. Health unit coordinators manage administrative tasks, organize patient records, and act as communication hubs within hospitals, making their role essential for efficient care.

International Blind Dog Day was founded in 2017 by Sarah Horne to advocate for the welfare of visually impaired dogs and to promote their adoption. Inspired by her own blind dog, Shammy, Horne launched the observance to dispel myths about blind pets, celebrate their adaptability, and highlight their ability to live full and loving lives. The day also coincides with the anniversary of the first successful corneal transplant performed on a dog.

International Hashtag Day marks the anniversary of August 23, 2007, when Chris Messina proposed using the “#” symbol on Twitter to organize conversations. Initially dismissed, the idea gained traction during the California wildfires when people used hashtags like #sandiegofire to share updates. Recognized by Twitter in 2018, the day celebrates a tool that has since become central to social media, activism, and digital communication worldwide.

Internaut Day commemorates August 23, 1991, when the World Wide Web, created by Tim Berners-Lee at CERN, was first made publicly accessible. While Berners-Lee had proposed the concept of a distributed information system in 1989 and developed the first website by 1990, this date marks the moment when ordinary users could explore the web beyond research institutions. The term “internaut,” blending “internet” and “astronaut,” describes skilled internet users who navigate the digital world, and the day highlights the web’s transformative role in communication, education, and commerce.

National Cuban Sandwich Day began in 2016 as a playful experiment by journalist Christopher Spata of the Tampa Bay Times, who wanted to see if he could create a food holiday. Though it started as a joke, the day quickly gained popularity and now celebrates the Cuban sandwich’s cultural heritage. With roots in Cuban immigrant communities of Florida, the sandwich typically features roast pork, ham, Swiss cheese, mustard, and pickles, with Tampa’s version adding salami—a detail that continues to spark friendly rivalry with Miami.

National Ride the Wind Day commemorates the achievement of August 23, 1977, when Bryan Allen piloted the Gossamer Condor to become the first human-powered aircraft to win the Kremer Prize. Designed by Dr. Paul MacCready, the lightweight plane successfully completed a figure-eight course at Minter Field in California, marking a milestone in aviation innovation. The day encourages people to embrace freedom and exploration, whether through flight-related activities or simply enjoying the feeling of wind in nature.

National Sponge Cake Day honors the light, airy dessert with origins in Renaissance Italy and Spain, where early recipes for sponge-like cakes, then called “biscuits,” were developed. The first English-language recipe appeared in Gervase Markham’s 1615 book The English Huswife. Today, sponge cakes are enjoyed worldwide in variations such as the Italian genoise, the French biscuit de Savoie, and Britain’s beloved Victoria sponge. Though the holiday’s exact origins are unclear, it offers a chance to appreciate one of baking’s most enduring creations.

Slavery Remembrance Day (officially recognized by UNESCO in 1997 as the International Day for the Remembrance of the Slave Trade and its Abolition) marks the 1791 uprising of enslaved people in Saint-Domingue, now Haiti. Beginning on the night of August 22–23, the revolt was pivotal in the eventual abolition of the transatlantic slave trade and the creation of Haiti as the first free Black republic. The observance underscores the resilience of those who resisted slavery and the importance of remembering the lasting consequences of colonialism and human exploitation.


💡

➡️  Have you already seen DigitalHyyge’s National Days Calendars 2025?

➡️  Complete list of August National Days

➡️  Complete list of September National Days

➡️  Curious to see more national and international celebrations? We have dozens of national days lists curated for you!

Categorized in:

Days,

Last Update: August 17, 2025