If you have driven Oracle Road through Oro Valley in the last few months, the Ashley Furniture sign is gone from the big-box anchor at the southwest corner of Oracle and Tangerine. Per the Oro Valley Marketplace tenant directory, Real Estate Daily News' 'Mountainside Fitness Expanding Into Southern Arizona' coverage, Connect CRE's 'Fitness Outfit Opening Three Tucson Locations,' Greater Phoenix In Business Magazine, and Mountainside Fitness's own Tucson-stay-connected page, that 45,000-square-foot building is being remodeled into the first of three Mountainside Fitness clubs the company plans to open in the Tucson metro in 2026. Two ground-up 40,000-square-foot standalone clubs are scheduled to join it — one inside the Houghton Towne Center at Old Vail and Houghton Road in Vail, the other inside Bourn Companies' planned Cascada retail center at the northeast corner of Twin Peaks Road and Interstate 10 in Marana. The three projects together represent roughly $33 million in development cost, are financed alongside Scottsdale-based STORE Capital, and are scheduled to open mid-to-late 2026. Here is a fully sourced May 15, 2026 walk-through for Oro Valley, Marana, and southeast Tucson residents, for buyers and sellers tracking what is opening in those submarkets, and for relocation shoppers comparing Tucson's amenity map against the rest of the Sun Belt. 3 clubs — Mountainside Fitness sites announced in the Tucson metro for 2026. 45,000 sq ft — Adaptive reuse at the Oro Valley Marketplace anchor box. 40,000 sq ft — Each of the new Vail and Marana standalone buildings. ~$33M — Combined development cost across the three Tucson-metro sites Who Mountainside Fitness Is Per Mountainside Fitness's 'Our Story' page and complementary coverage by the East Valley Tribune, Arizona Foothills Magazine, and Club Insider, Mountainside Fitness was founded in 1991 by Tom Hatten — then a 22-year-old Arizona State University student who put his $2,000 in savings into a single small club inside Mountainside Plaza in Ahwatukee. Three decades later the company has grown into Arizona's largest locally owned health-and-fitness brand, with 22-plus clubs and more than 150,000 members concentrated in the Phoenix metro. Per the Paradise Valley Independent and American Spa, Hatten handed day-to-day leadership to current president and chief executive officer Craig Cote on March 1, 2021 — thirty years to the day after the original Ahwatukee club opened — and remains involved with the company on expansion and charitable initiatives. The Tucson push represents the company's first set of clubs outside metro Phoenix. The Three Tucson-Metro Sites Oro Valley Marketplace — Oracle Road and Tangerine Road (45,000 sq ft, Adaptive reuse, Former Ashley Furniture box): Per Real Estate Daily News, Connect CRE, and the Oro Valley Marketplace tenant directory, Mountainside Fitness will take over the 45,000-square-foot former Ashley Furniture building at the southwest corner of Oracle Road and Tangerine Road inside the Oro Valley Marketplace. The site sits inside the active redevelopment footprint that broke ground in late 2025 to add multifamily housing, a hotel pad, and a refreshed retail mix to the long-underused regional center. Houghton Towne Center — Old Vail Road and Houghton Road, Vail (40,000 sq ft, Ground-up build, Southeast Tucson): Per Connect CRE and a Vail Voice community post confirming the announcement, Mountainside Fitness will build a 40,000-square-foot ground-up standalone club at the northeast quadrant of Old Vail Road and Houghton Road inside the Houghton Towne Center retail node. The location anchors the southeast Tucson submarket — the same Vail and Rita Ranch corridor that has absorbed a large share of the metro's recent new-home construction. Cascada Retail Center — Twin Peaks Road and Interstate 10, Marana (40,000 sq ft, Ground-up build, Northwest Tucson): Per AZBEX and Real Estate Daily News, Mountainside Fitness's Marana club will sit inside the planned Cascada retail center at the northeast corner of Twin Peaks Road and Interstate 10. The broader Cascada footprint is being advanced by Bourn Companies and Red Point Development under a Cascada II Specific Area Plan that would combine 752.5 acres under a single mixed-use master plan with commercial, residential, and light-industrial components. Possible Fourth Tucson Site — On the Roadmap (Future, Tucson metro, Not announced): Per Connect CRE and Greater Phoenix In Business Magazine, Mountainside Fitness has publicly flagged that it could add a fourth Tucson-metro club beyond the three already announced. No address, footprint, or timeline has been disclosed; the company is treating the initial three openings as the first phase of its southern Arizona presence. Why three locations at once matters: Mountainside Fitness is entering the metro the same way a national big-box retailer enters a new region — with simultaneous sites covering the geographic and commuter spread, rather than testing the market with a single club. Oro Valley anchors the northwest foothills, Marana anchors the northwest I-10 growth corridor, and Vail anchors the southeast new-construction corridor. For a single Tucson-area household, that puts a 40,000-to-45,000-square-foot Mountainside Fitness club within roughly a 15-to-25-minute drive of most of the metro's high-growth residential submarkets. What's Inside Each Club Per Mountainside Fitness's company amenities page, the company's southern-Arizona announcement materials, and Connect CRE's coverage, all three Tucson-area clubs are being built to the same operating template: indoor and outdoor workout spaces, three separate group fitness studios programmed with more than 70 classes per week, a Hyrox functional-training area, an interactive kids club, and a full locker-room build-out with steam rooms, infrared saunas, red-light therapy, and showers. The company's broader system also markets premium cardio and strength equipment, a cycle studio, and basketball or pickleball courts at select locations. Indoor-and-outdoor programming is a deliberate fit with the Sonoran Desert climate — the outdoor space is usable in the cooler bookends of the day across much of the year, even in the June-through-September heat window, which is one of the recurring lifestyle questions a relocation buyer asks when comparing Tucson against the rest of the Sun Belt. Investment, Financing, and Timeline Per Real Estate Daily News and Greater Phoenix In Business Magazine, total development cost per site is running in the $11 million to $12 million range, for a combined investment of roughly $33 million across the three Tucson-metro clubs. The financing partner is Scottsdale-based STORE Capital, a real-estate-investment-trust that has worked with Mountainside Fitness on prior projects elsewhere in Arizona. Opening windows for all three sites are described as 'mid-to-late 2026.' Adaptive reuse of the Ashley Furniture box at the Oro Valley Marketplace is generally faster to deliver than ground-up construction; the two 40,000-square-foot Vail and Marana buildings need to come out of the ground first, which is consistent with the late-2026 end of the published opening window. Prospective members and area residents should look directly to Mountainside Fitness's Tucson stay-connected page and the company's social channels for site-specific opening dates as the clubs near completion. How Each Site Fits Its Submarket The Oro Valley Marketplace site sits at the intersection of two of the northwest metro's busiest arterials — Oracle Road and Tangerine Road — and inside the redevelopment footprint that broke ground in October 2025 to add multifamily housing, a hotel pad, and a refreshed retail mix to the regional center. Per the Town of Oro Valley's published demographic profile, Oro Valley's population has grown past 47,000 across an incorporated footprint that runs from Tangerine south to the Pusch Ridge wilderness and includes master-planned communities like Rancho Vistoso, Stone Canyon, and Vistoso Trails. The Houghton Towne Center site sits at Old Vail Road and Houghton Road on the Tucson-Vail boundary inside zip code 85641, the southeast corridor that has anchored a meaningful share of new-construction inventory through the Rita Ranch, Civano, and Mountain View Ranch submarkets. The Cascada site at Twin Peaks Road and Interstate 10 sits inside Marana zip code 85742 along the Twin Peaks interchange — the same corridor that anchors Continental Ranch, Lazy K Bar Ranch, and Saguaro Bloom. Each of the three Mountainside Fitness sites lands inside one of the metro's most active residential submarkets rather than in a built-out infill node. The Oro Valley Marketplace Adaptive Reuse The Oro Valley Marketplace itself has a long, well-documented history as a regional center that opened in the late 2000s and spent the next decade-plus working through tenant transitions. Per the Town of Oro Valley, KOLD News 13, and the Oro Valley Marketplace tenant page, the current ownership broke ground in October 2025 on a redevelopment program designed to add multifamily housing, hospitality, and a refreshed retail mix to the existing footprint. Mountainside Fitness's 45,000-square-foot move into the former Ashley Furniture box is one of the highest-profile pieces of that re-tenanting story — a single-tenant adaptive reuse of an anchor box that has been quiet for several years, brought back into daily-use service as a fitness club rather than another big-box retailer. Adaptive reuses of this size are also relevant for buyers and sellers tracking commercial revitalization, because a 45,000-square-foot daily-traffic anchor reactivates the rest of the center's foot traffic in ways a vacant big-box pad does not. Practical note for current Oro Valley, Marana, and Vail residents: until the new clubs open mid-to-late 2026, Mountainside Fitness's network is still concentrated in metro Phoenix. The company's published practice is to make membership openings available to incoming Tucson-area members ahead of each club's grand opening, often with founding-member pricing windows. Look to the company's Tucson stay-connected page and each site's own social channels for those founding-member windows as the construction timelines firm up. Why a Three-Site Fitness Expansion Is a Real Market Signal Three 40,000-to-45,000-square-foot fitness clubs being entitled, financed, and built simultaneously inside a single metro by a private operator is the kind of capital commitment that does not happen on a guess. Per Mountainside Fitness's own characterization in Greater Phoenix In Business Magazine, the company describes the three Tucson sites as 'high-growth areas' — which is consistent with the underlying residential data: Oro Valley, the Twin Peaks corridor in Marana, and the Vail-Rita Ranch corridor in southeast Tucson have each been among the metro's most active new-construction submarkets through 2025 and into 2026. For buyers, that means the everyday amenity map of those three submarkets is getting denser, not thinner. For sellers in the same corridors, a 45,000-square-foot daily-use anchor opening within the typical home-search radius is a current, factual neighborhood-amenity update worth being aware of when discussing comparable listings and marketing copy. For relocation buyers comparing Tucson against Phoenix, Las Vegas, or Boise, the arrival of an Arizona-grown, 22-plus-club, 150,000-plus-member operator is one more data point that the Tucson metro's amenity infrastructure is being built out at scale. What to Watch Between Now and Opening Day Three things are worth tracking through the rest of 2026. First, vertical progress on the Vail and Marana standalone buildings — both are 40,000-square-foot ground-up projects, and the speed at which steel goes up at Old Vail and Houghton and at Twin Peaks and I-10 is the cleanest public indicator of which of the three clubs opens first. Second, the rest of the Cascada master plan: Bourn Companies and Red Point Development have been advancing the Cascada II Specific Area Plan through Town of Marana review, and the additional commercial, residential, and light-industrial components that ultimately land around the Mountainside Fitness pad will shape what the Twin Peaks corridor looks like through the end of the decade. Third, the announced-but-not-located fourth Tucson-metro Mountainside Fitness site — the company has flagged the possibility publicly but has not disclosed a submarket, a building type, or a timeline, and that fourth site, when it lands, is a real-time signal of which Tucson-area corridor is next on the company's growth map. Quick reference (May 15, 2026): Mountainside Fitness — three Tucson-metro clubs announced for mid-to-late-2026 opening. Site 1: 45,000-square-foot adaptive reuse of the former Ashley Furniture box at the Oro Valley Marketplace, Oracle Road and Tangerine Road, Oro Valley 85737. Site 2: 40,000-square-foot ground-up standalone at the Houghton Towne Center, Old Vail Road and Houghton Road, Vail 85641. Site 3: 40,000-square-foot ground-up standalone inside the Cascada retail center, Twin Peaks Road and Interstate 10, Marana 85742. Combined development cost roughly $33 million, financed alongside Scottsdale-based STORE Capital. Founded 1991 by Tom Hatten in Ahwatukee, Arizona. Current CEO Craig Cote (since March 1, 2021). 22-plus clubs and 150,000-plus members system-wide. Possible fourth Tucson-metro site on the company's roadmap. Sources Mountainside Fitness — 'Our Story,' 'Amenities,' 'Tucson Stay Connected,' 'Locations: Oro Valley,' and 'In the News' company pages (mountainsidefitness.com/our-story, mountainsidefitness.com/amenities, mountainsidefitness.com/tucson-stay-connected, mountainsidefitness.com/locations/oro-valley, mountainsidefitness.com/in-the-news). Real Estate Daily News — 'Mountainside Fitness Expanding Into Southern Arizona,' on the three Tucson-metro sites, the 45,000-square-foot Oro Valley adaptive reuse, the 40,000-square-foot Vail and Marana standalone buildings, the $11-to-$12-million-per-site development cost, the roughly $33 million combined investment, the STORE Capital financing relationship, and the mid-to-late-2026 opening window (realestatedaily-news.com/mountainside-fitness-expanding-into-southern-arizona). Connect CRE — 'Fitness Outfit Opening Three Tucson Locations,' on the three Tucson sites and the possible fourth Tucson-metro club (connectcre.com/stories/fitness-outfit-opening-three-tucson-locations). Greater Phoenix In Business Magazine — 'Valley Fitness Brand Enters Tucson with Multi-Site Expansion Across Oro Valley, Houghton, and Twin Peaks,' on the three submarkets, the amenity build-out, and the company's first-mover positioning (inbusinessphx.com). Metro Phoenix Alliance — 'Metro Phoenix Fitness Brand Enters Tucson Market,' January 2026, on the announcement (metrophoenix.com/2026/01/metro-phoenix-fitness-brand-enters-tucson-market). AZBEX — 'Plan Revisions in Marana Would Yield New Commercial and Residential Developments,' on the Cascada II Specific Area Plan, the 752.5-acre footprint, the Bourn Companies and Red Point Development sponsorship, and the planned phasing south to north (azbex.com). Oro Valley Marketplace — official tenant directory listing for Mountainside Fitness (orovalleymarketplace.com/directory/store/mountainside-fitness). KOLD News 13 — 'Oro Valley Marketplace breaks ground on new construction,' October 7, 2025, on the broader Oro Valley Marketplace redevelopment timeline (kold.com/2025/10/07/oro-valley-marketplace-breaks-ground-new-construction). Town of Marana — Marana Development Update 2026 newsroom entry, on active Twin Peaks and Tangerine corridor permitting (maranaaz.gov/Newsroom-Entries/2026/Marana-Development-Update). Vail Voice community page — Houghton Towne Center confirmation post for the Vail location (facebook.com/thevailvoice). Paradise Valley Independent / Your Valley — 'Hatten steps down as Mountainside Fitness CEO,' on the March 1, 2021 leadership transition from founder Tom Hatten to Craig Cote (yourvalley.net). East Valley Tribune — 'Idea turns ASU student into Mountainside Fitness CEO,' on Tom Hatten's 1991 founding of the first Mountainside Fitness in Ahwatukee with $2,000 in savings while attending Arizona State University (eastvalleytribune.com). American Spa — 'Mountainside Fitness Names Cote as CEO; Hatten to Focus on Expansion, Charitable Work,' on the current leadership structure (americanspa.com). All data current as of May 15, 2026. This post is for informational purposes only and is not an offer to sell or a solicitation of an offer to purchase real estate, and is not a solicitation of fitness-club membership.