Construction on Maryland's Purple Line—a 16-mile, 21-stop light rail connecting Bethesda to New Carrollton—will begin later this year. Service is expected to begin in 2022. Developers are beginning to build some huge projects along the rail line, attempting to cash in on the desire to live and work near mass transit. Here are the 10 biggest projects that'll do just that.

Carr's Apex Building Redevelopment

courtesy of Executive Space Solutions

Developer: Carr Properties

Location: 7272 Wisconsin Ave at upcoming Bethesda Purple Line station

Details: Three towers: two residential and one office

Timeline: Sketch plan approval in February, no construction date announced

In November, Carr Properties bought the 164k SF Apex Building from the American Society of Health System Pharmacists for $106M. Carr is planning to build three towers and looks to build up to the 250-foot height and 937k SF density maximums. This project will sit right above the western terminus of the Purple Line.

Chevy Chase Lake

Developer: Bozzuto, Chevy Chase Land Co

Location: Connecticut Avenue in Chevy Chase, near the Purple Line's Connecticut Ave station

Details: Three buildings totaling 530 residential units; 50k SF grocery store

Timeline: Construction to begin in 2018

Developers submitted detailed plans for this project—which aims to create a mixed-use town center—to the Montgomery County Planning Department last week. The first building will include 283 residential units and be anchored by a 50k SF grocery store and an additional 19k SF of retail.

Elizabeth Square

Lee Development Group

Developer: Lee Development Group, Montgomery County Housing Opportunities Commission

Location: Fenwick Lane in Silver Spring, near upcoming Woodside Purple Line station

Details: 907 housing units, 45k SF of community uses

Timeline: Received Planning Board approval in July 2015, no construction timeline set

This $200M project at the site of the 50-year-old Elizabeth House senior living facility will be built in three phases. After the first, 15-story, 277-unit Elizabeth House III is built, the seniors in the original Elizabeth House will be moved to the new building and their old home will be replaced by the 19-story, 330-unit Elizabeth House IV. The 24-year-old Alexander House will also be renovated as part of the project. The project will also include a wellness center, artist workspace and rooftop garden.

The Blairs Redevelopment

The Tower Companies

Developer: The Tower Cos

Location: Near the existing Silver Spring Metro station and upcoming Purple Line station

Details: 2,800 apartment units, 125k SF of retail, 200k SF office, 200-room hotel

Timeline: Full construction could take more than 10 years

This massive $650M redevelopment of the 1950s-era Blairs development will include a five-acre public courtyard that will support concerts, farmers markets, movie screenings and more. The Montgomery County Planning Board approved the first phase in 2014, construction began in early 2015 and is slated to be completed in early 2017.

Metro Plaza

Courtesy: Maikel-Hollins Development Co

Developer: Maisel-Hollins Development Co

Location: East-West Highway directly adjacent to Silver Spring Metro, upcoming Purple Line Station

Details: Two towers with 552 units, 14k SF of retail

Timeline: Construction won't begin until around 2020

Because of its proximity to the Purple Line station, Metro Plaza won't begin construction until after the Purple Line is completed. MDC's Harvey Maisel tells Bisnow he thinks people are just discovering Silver Spring, with its convenient proximity to public transportation and the beltway.

"It's been a hell of an opportunity to create this development, which will be the crown jewel of Silver Spring," Harvey says.

The Hotel at UMD

A rendering of the $150M Hotel at UMD, set to open in September

Developer: Southern Management Corp

Location: Route 1 in College Park, near upcoming East Campus Purple Line station

Details: 297 rooms, 43k SF of meeting space

Timeline: Set to open in January 2017

College Park's largest development in recent memory, this $150M project is expected to increase economic activity by $62M per year. The hotel, directly across Route 1 from the campus, will feature four new ground-floor businesses: Franklin's Oyster Bar and Grill, Potomac Pizza, Bagels 'n Grinds, and Elizabeth Arden's Red Door spa. Southern Management CEO David Hillman will be a speaker at Bisnow's Future of Prince George's County event next month.

Ron Paul's College Park Development

University of Maryland

Developer: Ronald D. Paul Cos

Location: 4301 River Road, College Park, adjacent to existing College Park Metro Station and upcoming Purple Line station

Details: Five stories with 370 residential units, 5k SF of retail, 395 parking spaces

Timeline: LOI signed in October, construction timeline unknown

Just the latest in College Park's apartment boom, this 370-unit project is being build by a 1979 UMD alum, EagleBank Chairman/CEO Ron Paul. Unlike many of the recent developments near Route 1 that lure students off campus, these metro-adjacent apartments will have an eye toward recent graduates and professionals.

Gilbane's College Park Development

Gilbane Development Co

Developer: Gilbane Development Co

Location: Adjacent to existing College Park Metro station, upcoming Purple Line station

Details: 430 units, 12k SF of retail

Timeline: Term sheet signed June 9 with landowner WMATA, construction date not yet announced

The same company that built UMD's Xfinity Center (née Comcast Center) and its new Physical Sciences Complex, Gilbane is now shifting its focus off campus and building 430 Metro-adjacent apartments with ground-floor retail. WMATA released an RFP last July for the six-acre parcel containing a parking lot right outside the Metro station, and just this month announced Gilbane had won the bid.

Riverdale Park Station

Cafritz Enterprises

Developer: Cafritz Enterprises

Location: Near intersection of Baltimore Avenue and East-West Highway, near upcoming Riverdale Park Purple Line station

Details: 37 acres, 850 apartments, 119 townhouses, 120-room hotel, office building, more than 200k SF of retail

Timeline: Broke ground in May 2015, expected to open in the next year

This massive mixed-use project will feature Prince George's County's first Whole Foods. Additional retail includes Jersey Mike's, Habit Burger, Burton's Grill, Bella Beach Spa and Old Line Bank.

New Carrollton's TOD

Gensler

Developer: Berman Enterprises, Urban Atlantic, Forest City Washington

Location: Near the existing New Carrollton station and future Purple Line station

Details: 97k SF of offices, 556 apartments and 61k SF of retail from Berman; 1.1M SF of office, 1.3M SF of residential, and 150k SF each of retail and hotel space from Urban/Forest City

Timeline: Phase 1 of Berman's project completed, Phase 2 began development early this year; the JV to be built over 15 years

Two projects that sit adjacent to each other will transform the area around the eastern terminus of the line. The first phase, a 97k SF office building, now home to the HQ for the Maryland Department of Housing and Community Development, is done. Still to go are thousands of apartment units, hundreds of thousands of office and retail square footage, and at least one hotel.