Landmark on Main Street is a not-for-profit community center dedicated to strengthening the spirit of community by presenting and promoting opportunities for cultural, educational, recreational, social and civic activities for the benefit of the people of Port Washington and neighboring communities.

Landmark on Main Street is a national, state and local historical landmark. Built in 1908, thousands of Port Washington students were educated in what was then known as the Main Street School until it closed in 1985. Thanks to a true grassroots effort, Landmark opened its doors as a community center on November 5, 1995. With 59 units of affordable housing for seniors and the developmentally disabled on our upper floors, Landmark is also home to the Port Washington Youth Council's Teen Center, the Port Washington Parent Resource Center, the Port Washington Children's Center and the Doctors' Gymnasium.

The Jeanne Rimsky Theater is also housed at Landmark. Used from 1916-1985 as the Main Street School auditorium, the Jeanne Rimsky Theater has been renovated to provide 425 comfortable seats, a state-of-the-art sound system, a magnificent Steinway Concert Grand D piano, and an intimate setting to connect with the performers from anywhere in the theater.

Landmark has hosted sold-out performances including musicians such as The Bacon Brothers, Joan Osborne, Broadway's Brian Stokes Mitchell, Christine Ebersole, Kelli O'Hara and Brian d'Arcy James, Latin-Pop star Raul Malo, and folk/rock icons Judy Collins, Steve Earle, Richie Havens, Janis Ian, Lucy Kaplansky, Shelby Lynne, Rickie Lee Jones, Jorma Kaukonen, The Kingston Trio, Tom Paxton, Jean Ritchie, Martin Sexton, Richard Shindell, Suzanne Vega and Dar Williams.

The Jeanne Rimsky Theater also offers affordable rental space where a variety of events take place, such as dance performances, film screenings, opera rock concerts, body building exhibitions and much more.