It’s been 50 years since the Westport Arts Center first opened its doors and, to celebrate, organizers are planning a sneak peek of what their new space will look like.

The grand opening of the new, significantly larger facility at 19 Newtown Turnpike is currently scheduled for September, and in anticipation of that move the current Riverside Avenue location will close its doors at the end of June.

But right before that happens, they’re holding a 50th anniversary gala, scheduled for May 18.

Executive Director Amanda Innes teased the gala — and the planned first exhibition at the new space — saying it would be something unique to the state.

“Our first exhibition in the new space will be something never before seen in Connecticut,” she said.

The move will allow the Westport Arts Center, originally incorporated in 1969 as the Westport-Weston Arts Council, to host large-scale events. There will also be a cafe, lounge and a library.

It’s actually the second such move in the organization’s history. Until 1999, the Westport Arts Center was located at the corner of Morningside Drive South and Boston Post Road. Three years later, the 3,600 square-foot building on Riverside Drive became the arts center’s home.

Now, 50 years after its initial incorporation, the Westport Arts Center will be moving into a building with its own history.

The castle-like building at 19 Newtown Turnpike was Martha Stewart’s headquarters and television studio for a time. Before that, there were munitions and aircraft parts manufactured and stored there.