Martin Luther King, Jr. Day of Service is a federal holiday that takes place on the third Monday of January. It’s a day to honor the life of Dr. Martin Luther King, Jr. by encouraging people to volunteer and improve their communities. The holiday is also known as a “day on, not a day off.”

The following events will take place Jan. 20 around the Lehigh Valley.

•MLK Celebration Committee Walk of Unity, noon at the flagpole on Lehigh University, symbolizing Dr. King’s enduring message of solidarity. All are welcome, no registration required.

•Bethlehem NAACP Annual MLK Celebration, noon at St. John A.M.E. Zion Church, 718 Pawnee St., Bethlehem. The theme is “The Battle is Not Ours, It Is the Lord’s” and the keynote speaker is Shanise M. Palmer. This event is free and open to the public, though parking is limited; refreshments will be served.

•The Allentown Art Museum, 31 N. Fifth St., Allentown, will feature art making, live musical performances, poetry and more 11 a.m. to 5 p.m. Admission and parking are free.

•Volunteer Center of Lehigh Valley has meaningful service projects such as organizing food drives, cleaning parks or assembling care packages for those in need. Visit their website at https://www.volunteerlv.org/mlk or call 610-807-0336.

•Martin Luther and Coretta Scott King Memorial Project Day Light Vigil at the MLKCSK Memorial, Union Street and Martin Luther King Jr. Drive, Allentown, 9:30 a.m.

•Rebuild The Dream MLK Day program 11 a.m. to 12:30 p.m. at Union Baptist Church, 302 N. Sixth St., Allentown. Includes a program of music, spoken word and dance. Free and open to the public. A freewill offering will be received.

•Cedar Crest College Martin Luther King Jr. Day Annual Breakfast, 9-10 a.m. at Cedar Crest College, 100 College Drive, Allentown, Tompkins College Center.

•National parks will waive entrance fees for everyone Jan. 20. Service projects are available at national parks on that day.

•Lehigh Valley Zoo will be open 10 a.m. to 3 p.m. Jan. 20. Visitors can learn about the zoo’s dream: a safe environment for animals and people alike. They will have conservation themed crafts and activities for guests and the opportunity to meet and greet one of their ambassador animals up close throughout the day.