The supermarket space at Route 347 and Crystal Brook Hollow Road has been empty since King Kullen closed in June 2019. That's more than seven years as of this October. The plan to fill it is now under construction, and Whole Foods Market will be the anchor. Most coverage stops there, but Whole Foods is only one part of a rebuild that is scheduled in stages. Regency Centers, the owner, laid out a sequence that runs from late 2026 through 2028. The shops that are open today are expected to stay open while it happens.
So for people who shop there every week, the change will come in pieces. New façades, a repaved lot and a few new storefronts will show up over many months. There won't be one grand-opening day.
A shopping center that never closed for its rebuild
Regency Centers is a real estate investment trust based in Jacksonville, Florida. It bought the property, then called Mount Sinai Shopping Center, in January and renamed it Crystal Brook Corner. Newsday reported in July 2026 that the redevelopment will cost $59 million. Site work and some demolition started in March. Many shops were still operating when the paper visited during construction.
The formal groundbreaking came after the crews had already started. Councilwoman Jane Bonner attended the ceremony, which the Town of Brookhaven announced on June 15, 2026. The Brookhaven Planning Board had approved the site plan back in December 2025, according to Newsday.
Regency lists the center at 125,348 square feet in total. The Town and Regency give the address as 5507 Nesconset Highway. Newsday uses 5499 Nesconset Hwy. Either way it's the same plaza, and its west side runs along Crystal Brook Hollow Road.
The order things arrive in
Regency spokeswoman Chelsea DuDeVoire gave Newsday the schedule:
"Building exteriors and sitework will be substantially complete by the end of the year, with interior work, final paving, landscaping, and signage complete by spring 2027."
Here is how that schedule plays out from now on.
- Now through December 2026. Crews keep working on the façades, the site and the new freestanding building. Regency expects this outside work to be substantially done by the end of the year.
- Winter into spring 2027. Work moves indoors. Final paving, landscaping and new signs are due by spring 2027. That is the point when the lot and storefronts should look finished.
- During 2027. The first three new tenants with signed leases are expected to open. They are Nothing Bundt Cakes, PACFE Nails & Spa and BYou Laser Clinic.
- Through 2027 and into 2028. Other new tenants open on a rolling basis, DuDeVoire said.
Whole Foods doesn't appear on that list because it has no announced date. Greater Long Island reported in July 2026 that no opening date had been set. TBR News Media also reported that no official opening date has been set. The spring 2027 date covers the shopping center's interiors and grounds. It isn't a promise about when the grocery store's doors open.
Where each new piece sits on the lot
The rebuild touches four parts of the property. Each one changes how the center works when you're running errands.
| Part of the center | Approximate size | What's planned | Status as of July 2026 |
|---|---|---|---|
| Former King Kullen space | 35,500 sq ft | Whole Foods Market, exterior and interior fully redone | Planned anchor, no opening date |
| New building at the center's entrance | 5,080 sq ft | Two quick-service restaurants | Tenants not yet named |
| First floor of the two-story building, vacated by Rite Aid | About 10,950 sq ft | PACFE Nails & Spa plus three other small shops | One tenant named |
| Former loading area next to the Rite Aid space | Not specified | Landscaped patio | Planned |
The new restaurant building sits at the entrance, which Regency called the center's "prime location." DuDeVoire said both national and local restaurants have shown strong interest, but Regency was "not in a position to announce those tenants yet." The upstairs of the former Rite Aid building still has office tenants. Only the ground floor is being turned into shops.
Whole Foods will be its ninth Long Island location, TBR News Media reported.
The tenant mix will shift over time
According to Newsday, most of the center's current tenants are locally owned small businesses. Regency has said it plans to move toward a mix of national, regional and local businesses. That would include boutique fitness studios, restaurants, and personal and pet services.
The leases signed so far fit that description. A bakery chain, a nail salon and a laser clinic are personal-service and treat stops that people combine with a grocery run. DuDeVoire said interest in the remaining space has been strong and that Regency expects to announce more businesses throughout the year. Because tenants will open on a rolling basis into 2028, the full lineup could take more than a year to settle after construction ends.
A mile up the road, Mavi Grill is making its own move
Route 347 isn't the only place in Mount Sinai where a familiar business is changing addresses. Mavi Grill, the Mediterranean restaurant that owner TJ Kola has run for 13 years, is moving about a mile up the road. Its new home is a brand-new plaza at 515 Route 25A, at the foot of the entrance to Mount Sinai High School. The current restaurant is at 749 Mount Sinai-Coram Road, at the corner of North Country Road.
The move brings a few changes, according to Greater Long Island's August 2026 profile:
- A new name. The restaurant is rebranding as Mavi Mediterranean Grill.
- Beer and wine for the first time.
- About twice the space. There will be room for 40 to 50 seats inside and three or four tables outside.
- Almost all new equipment. Kola said he's bringing only a couple of refrigerators from the old kitchen.
The new plaza is also expected to include a bakery, a barbershop and a wine store. Their names haven't been reported.
Mavi's timeline also ran long. Kola signed his lease in November 2024 and expected keys within six months, but he didn't get them until June 1, 2026. In August he said he was aiming to open in the fall, "hopefully in October." As of early October, no announcement confirms that the new location has opened. Until one does, the move is still planned. Nothing has been reported about what will go into the old corner spot.
What this fall and winter look like on the ground
For the next few months, both projects will mostly be visible from the road. The center on Route 347 will look like a construction site with open stores. Exterior and site work are due by year-end, and paving and landscaping won't be finished until spring 2027. Parking lot work comes during that window, so the lot will likely change from one month to the next.
Some changes on the corridor are already done. On September 21, 2026, the Town of Brookhaven announced it had finished installing 16 decorative streetlights along Route 25A and Route 347. Some of them run along Route 25A westbound from Crystal Brook Hollow Road to the Route 347 split, right next to the shopping center. Further along the same road, Sophia Rose Home & Furniture held its grand opening at 561 Route 25A on June 24.
Here is where things stand in October 2026. The shops at Crystal Brook Corner are open during construction. Whole Foods is the planned anchor but has no opening date. Three smaller tenants are set for 2027, and two restaurant tenants are still unnamed. Mavi's move to 515 Route 25A is planned but not confirmed open.
Changes like a new grocery anchor and refilled storefronts can affect how buyers see a part of town, and they're worth factoring in if you're thinking about listing in the next year or two. If you'd like to know how the Crystal Brook Corner timeline fits with your own plans, the Dawson Realty Team can walk you through what nearby homes are doing now. You can start with a Free Home Valuation.
