There’s a race under way to build half a billion dollars’ worth of office towers overlooking the Schuylkill River in Conshohocken, and a Chester County company intends on staking its next big claim there.

“There are only a few sites that can accommodate a Class A build-to-suit, and Conshohocken has five of them,” Binswanger broker Scott Gabrielsen said in a recent Philadelphia Business Journal report.

O’Neill Properties Group, the King of Prussia developer specializing in the luxurious transformation of abandoned and underutilized industrial sites, is proposing to expand on its key role in Conshohocken’s earlier development, having built the Millenium complex more than a decade ago.

Its plans center on the 300,000-square-foot Millenium Four, though other developers are proposing even more ambitious projects, like Equus Capital Partners‘ 330,000-square-foot office building and Keystone Property Group‘s 300,000-square-footer combined with a 200-room hotel and old firehouse to brew pub conversion.

The smaller 260,000-square-foot Seven Tower Bridge building by another instrumental early Conshohocken developer, Oliver Tyrone Pulver, and 82,000 square feet by E. Kahn Development nearby are also in the running.

Read more about the red-hot Conshohocken market and the reasons behind its latest wave of new development in the Philadelphia Business Journal here.