Memorials may be simple; memories may not. Both are important.

Yesterday was the 25th anniversary of 9-11. One of the many thoughts that crossed my mind was the reality that most people under the age of 25 were not alive and will not have a firsthand memory of that day.

We can debate whether that’s good or bad. The best answer is, “Both.”

Those under 25 depend on the memorials and monuments we who were alive have created.

I did not know until yesterday about the memorials at Boston’s Logan Airport. One of the more subtle ones is the US flags that fly above Gates B32 and C19. These are the gates that the two aircraft departed from that fateful morning.

According to a recent Boston Globe article, when Logan’s official memorial was dedicated in 2008, then-Massport Chairman John Quelch shed further light on the flags’ origins.

“Both memorials appeared spontaneously, raised by airport and airline employees without fanfare or ceremony,” he said. “These two memorials are one and the same. And there is no grander memorial. That memorial is the flag of the United States of America.”

If there’s ever a second edition of my book, Memorials, Monuments, and Memories, there might well be an added chapter. The grandest memorials are the simplest.

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You don’t have to be under 25 to appreciate some facts and memories. Here are a few to get you started.

• The Tunnel to Towers Foundation is by itself a memorial that proves “We will never forget.
• The World Will Never Forget 9/11 is exactly what it sounds like, an entire blog dedicated to keeping the memory of that day alive, from the Memorial Plaza to the stories behind it.
• Ephemeral New York has spent years documenting the small, personal memorials tucked into corners of the city, the ones you’d walk past without noticing unless someone pointed them out.

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