Twenty years ago this week, one of the darkest days in American history occurred: the terror attacks on Sept. 11, 2001.

Nearly 3,000 Americans died that day, while thousands of others suffered injuries, and people throughout the country faced a traumatic and scary new reality.

The anniversary of 9/11/01 is Saturday, and it’s being marked with ceremonies, readings, and reflections to honor those who died and the first responders who continue to keep us safe.

Here’s where to commemorate the 20th anniversary of 9/11 throughout the Philadelphia region.

September 11 Observance at Flight 93 National Memorial

The Flight 93 National Memorial commemorates the crash of United Airlines Flight 93 on Sept. 11, 2001. For the 20th anniversary of 9/11, the Shanksville, Pa., site (about four hours from Philly) has a week of events that began Tuesday, and concludes Sunday. During the main event, on Saturday, Sept. 11, the names of the flight crew and passengers will be read during a wreath-laying, bell-ringing ceremony. The reading will begin at 10:03 a.m., the time when Flight 93 crashed. Then, in the afternoon, the Johnstown Symphony Orchestra will perform a memorial concert. Additional events throughout the week include Friday’s luminaria ceremony and Sunday’s “Witness to History” speakers, featuring first responders. (Free, through Sept. 12, 6424 Lincoln Hwy., Stoystown, nps.gov)

» READ MORE: How Somerset County residents honor United Flight 93

Remembrance Ceremony at Betsy Ross House

Mayor Jim Kenney offers remembrance remarks at the Betsy Ross House’s 9/11 ceremony, along with other notable members of the community. The day starts with a processional from the Fireman’s Hall Museum to the Betsy Ross House where there will be a flag folding ceremony and bell ringing. (Sept. 11, 9:59 a.m., 239 Arch St., historicphiladelphia.org)

Remembering 9/11 20 Years Later

Lower Makefield’s Garden of Reflection is home to two ceremonies on 9/11. The morning begins with a bell-ringing ceremony honoring the fallen and a time for reflection. The main event, the Remembrance in Light ceremony, occurs in the evening and aims to create a sense of hope during a dark day through candle lighting, music, and remarks from speakers. You can also tune in to a livestream on the Lower Makefield Township YouTube channel. Tours of the garden will be available throughout the day. (Sept. 11: 8:30 a.m. bell-ringing ceremony; 7 p.m. Remembrance of Light ceremony, 1950 Woodside Rd., Lower Makefield, 9-11memorialgarden.org)

9/11 Heroes Run

The Travis Manion Foundation’s 9/11 Heroes Run takes place Saturday at the Navy Yard in South Philly and honors those who died during the attacks on 9/11, along with the first responders who have served our country. There’s both a 5K and one-mile course, and you can choose to run, walk, or jog. (Sept. 11, 4747 S Broad St., travismanion.org)

Black Clergy of Philadelphia and Vicinity’s 9/11 Ceremony

The Mt. Airy Church of God in Christ welcomes all for a 9/11 service led by the Black Clergy of Philadelphia and Vicinity that honors those who died in the 9/11 attacks and the Sept. 11 first responders. (Sept. 11, 10 a.m., 6401 Ogontz Ave.)

Haverford First Fest Music Festival

Haverford honors first responders on the 20th anniversary of Sept. 11 with a free music festival at Eagle Road and East Hathaway Lane. Local musicians, including the Scott McClatchy Band, Suzie Brown, and Dels Groove perform on the festival stages — one indoors at Kelly Center and one outdoors. Tributes to police, EMS, firefighters, doctors, and nurses are planned throughout the day. (Sept. 11, Eagle Road and East Hathaway Lane, Havertown, kellymusicforlife.org)

Gloucester County Patriot Day Ceremony

Gloucester County honors the 20th anniversary of 9/11 and all of those who died, specifically those from the Gloucester County community. The county’s hour-long ceremony will feature a wreath laying, bell ringing, and visits from 9/11 victim’s families and first responders. (Sept. 11, 8:30 a.m., Chestnut Branch Park, 401 Main St., Mantua, gloucestercountynj.gov)

» READ MORE: These Philadelphians share their memories of 9/11, two decades later

Remembrance Ceremony in Burlington County

Two New Jersey first responders lead a remembrance ceremony outside the Burlington County Emergency Service Training Center. The commemoration includes a wreath-laying ceremony, a bagpipe processional, and a reading of the names of the victims from Burlington County. A piece of steel from the World Trade Center will also be on display. (Sept. 11, 11 a.m., 53 Academy Dr., Westampton, co.burlington.nj.us)

9/11 Remembrance Ceremony at the Ocean City Tabernacle

At the Ocean City Tabernacle, music, reflections, and prayer will be the basis of a special ceremony. (Sept. 11, 6 p.m., 550 Wesley Ave., Ocean City, oceancityvacation.com)

Downtown Wildwood Remembers September 11

At Byrne Plaza in Wildwood, first responders and those who died during the 9/11 attacks are honored at a free outdoor ceremony featuring the City of Wildwood Honor Guard, local speakers, and more. (Sept. 11, 10:30 a.m., 3400 Pacific Ave., Wildwood, wildwoodsnj.com)

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