After a nearly four-decade drought, two separate air-rights projects with a combined cost of $1.7 billion are taking shape, including one set to be a major life sciences hub in the city.

Massachusetts transportation officials will pursue plans to tear down a 1960s MassPike viaduct as part of the massive highway reconfiguration and redevelopment project.

The 1.3-million-sq-ft Fenway Center air-rights project in Boston includes a 90,000-sq-ft deck over the Massachusetts Turnpike next to Fenway Park.

An agonizing civic decision must be made over whether to rebuild in the air or at grade.

Contractors in Boston broke ground on Jan. 30 at the long-anticipated, $240-million Fenway Center megadevelopment.

The long-anticipated groundbreaking of the $240 million Fenway Center megadevelopment was on Jan. 30 in Boston.

A successful air-rights project has not been built over the Massachusetts Turnpike since Copley Place opened in downtown Boston in 1983.