Construction has begun on a new section of a bike path that will eventually span 44 miles from Oceanside to San Diego.
The Rose Creek Bikeway will link University City to Mission Bay and downtown San Diego when it opens in early 2020.
On Thursday, SANDAG officials marked the groundbreaking for the project that will begin at the north end of Santa Fe Street and fill a two-mile gap while connecting to an existing bike path.
Officials consider the area one of the most heavily-traveled bike corridors in the region.
"By providing residents with more travel choices, we are fulfilling our TransNet commitment to taxpayers and strengthening our overall regional transportation network," said SANDAG Chair and Del Mar City Councilmember Terry Sinnott.
TransNet is the regional half-cent sales tax approved by voters to fund transportation improvements in the region.
Two percent of the annual revenue from the tax is allocated to the Bicycle, Pedestrian, and Neighborhood Safety Program.
SANDAG plans to build undercrossings at Interstate 5 and Mission Bay Drive as well as a 260-foot bridge over Rose Creek as part of the project.
The construction is part of the ongoing Coastal Rail Trail.