• Lawrence Library September Book Sale,  2751 Brunswick Pike, 10:00AM - 4:30PM
  Thousands of gently used books for all ages will be on sale at the Friends of the Lawrence Library Book Sale, running Friday, September 19 through Monday, September 22 at the Lawrence Headquarters Branch in Lawrenceville. Admission is free, with special $5-a-bag deals on Sunday and Monday—just remember to bring your own bag and pay by cash, check, or Zelle.

• D&R Greenway's Native Plant Sale, Johnson Education Center, 12:00 - 4:00PM
  Visit D&R Greenway’s Native Plant Nursery next to the Johnson Education Center in Princeton, where knowledgeable staff and volunteers will help you choose the best native plants for your yard. Admission is free, no registration is required, and every plant you add supports pollinators, wildlife, and the fight against climate change. More info here
• Highland Park Farmers Market, 212 Raritan Avenue, 11:00AM - 5:00PM
  The Highland Park Farmers Market is a community hub where you’ll find fresh local produce, meats, dairy, baked goods, and artisan foods, alongside live music, activities, and seasonal celebrations. Open every Friday from February to December, the market also  offers access to community resources like health services and library programs. More info here
• Blue Moon Acres Farmers Market, 11 Willow Creek Drive, 9:00AM - 5:00PM
  The Blue Moon Acres Farmers Market runs every Friday and Saturday April to December, and features a variety of locally produced foods and goods from other farms. This season, enjoy Owowcow ice cream, Calkin's cheeses, and other fresh produce straight from the farm. More info here

• Manila Madness 5k Freedom Run, John Basilone Memorial Park, 10:00AM - 12:00PM
  Join the Manila Madness 5K Freedom Run/Ruck, a USATF-certified event honoring Marine Corps legend Gunnery Sergeant John Basilone and the sacrifices of America’s heroes. Whether you run, ruck, or cheer from the sidelines, it’s a powerful way to test your endurance and pay tribute to Basilone’s courageous spirit. Tickets start at $30, include a t-shirt and medal for participating, and can be purchased here
•  Campus Art Tours, Princeton University Art Museum, 2:00 PM - 3:00 PM 
  Take a guided outdoor walking tour of one of the nation’s most significant collections of 19th- and 20th-century sculpture, featuring works by artists like Henry Moore and Louise Nevelson. Tours are free, held rain or shine, stair-free, and no RSVP is needed—just meet in front of Nassau Hall. More info here
• Hopewell Harvest Fair, Hopewell Elementary School, 9:45AM - 4:00PM
  The Harvest Fair returns to Hopewell Elementary School on Saturday, September 20, from 9:45 AM to 4:00 PM, bringing a full day of old-fashioned fun while supporting local non-profits. Enjoy hay rides, pony rides, a petting zoo, games, contests, local food, and more at this beloved community tradition. Free to attend, more info here
• Vehicle Day!, West Windsor Library, 10:00AM - 12:00PM
  Bring the family to the library for a hands-on “Touch a Truck” event, where kids can explore fire, police, EMS, and postal vehicles and meet the people who operate them. With crafts, a themed story time, and fun for all ages, this outdoor event runs rain or shine with no registration required.
• Scavenger Hunt in the Mapleton Preserve, 145 Mapleton Road, 10:00AM - 11:30AM
  Join the Friends of Princeton Nursery Lands for a free nature- and history-themed scavenger hunt at Mapleton Preserve/D&R Canal State Park. All ages are welcome to explore the trails, discover hidden treasures, and take home a free FPNL tote. Completely free to enter, more info here

• Bluegrass Music Performance, Bouman-Stickney Farmstead, 1:00PM
  Enjoy an afternoon of live bluegrass as Ed Jankiewicz and the Holland Brook Hillbillies perform inside the Wade-Wycoff Barn at the Bouman-Stickney Farmstead on Sunday, September 21, at 1:00 p.m. This free, family-friendly event blends music, history, and jam sessions that celebrate the roots and evolution of bluegrass, with donations gratefully accepted. More info here
• Family Matinee Series: New York International Children’s Film Festival, Princeton Garden Theatre, 10:00AM
  A series of short films will be aired at the Princeton Garden Theatre. All family friendly, these films are from the New York International Children's Film Festival. Tickets start a $5/person, and can be purchased here
• Fall Equinox Folk Festival, 452 Herrontown Road, 3:00-5:00PM
  The Chivalrous Crickets return to the gardens of Veblen House with a lively concert blending Celtic, English, and American folk music, storytelling, and country-style dancing. Enjoy seasonal crafts, native plants, an Einstein Begonia raffle, refreshments from May’s Pop-up Café, and a festive day outdoors. Tickets start at $10 and can be purchased here
• Annual Pop-Up Beer + Wine Garden, 102 Witherspoon Street, 2:00PM - 5:00PM
  Raise a glass to the arts with local brews, wine, live music, grilling, and games at this community favorite event. All proceeds benefit the arts council’s outreach programs, helping provide high-quality, accessible art experiences for youth, families, LGBTQ+ teens, and seniors in our community. Tickets start at $60, and can be purchased here