As the bushwalking season descends, an historical bridge which overlooks North Harbour in Balgowlah that was constructed in the mid-1920s has been restored and has reopened.

Northern Beaches Council General Manager Mark Ferguson said the 90 year-old Clarence Street Bridge is one of the most recognisable landmarks along the Manly Scenic Walk.

"I encourage locals and visitors alike to explore the bushwalk which leads trekkers to the 90-year-old timber Clarence Street Timber Bridge, then through to Manly," Mr Ferguson said.

"At the end of the walk people can enjoy the café and restaurant scene and take-in the surf culture and sites along the Corso and foreshore."

Mr Ferguson said the wooden pedestrian bridge had been closed after a major assessment of the bridge structure concluded that it was irreparably structurally unsound and dangerous.

"The bridge has now been rebuilt using select Australian Hardwood from Lismore to meet current Australian Building Standards," he said.

"With routine Council inspections and appropriate maintenance it should serve the community for another 90 years."

A registered surveyor was commissioned by Council to check property boundaries and confirm the precise, correct location of the replacement bridge. Northern Beaches Council contractors Sullivans Constructions were responsible for its restoration.

The original Clarence Street Timber Bridge was built in mid-1920s by the former Manly Council.

The Council advertised for tenders to build the footbridge in February 1923, and it was shown in the estate subdivision plan for the Waterfall Estate of January 1924.

The eminent Australian novelist Kylie Tennant, in her autobiography The Missing Heir, stated that as a child she would occasionally see platypus playing at the waterfall at North Harbour, which would have been early 1920s, and armies of blue crabs on the sand-flats.