Work has started to look at restricting access to motor traffic through Vallee des Vaux on Sundays, following approval from the Roads Committee.
An event is due to be held later this year and traffic-calming measures could be put in place from Spring 2021.
It's aimed at encouraging more walking and cycling throughout St Helier's green lanes.
John Baker from the Committee instigated the idea and invited Deputies Inna Gardiner and Rob Ward, a Cycle4Jersey member and a group of local residents to walk the valley and discuss road safety and traffic-calming measures.
Mr. Baker says there's been a lot of support for the move.
"We had a meeting with the residents and they were absolutely thrilled and all on board.
"We've got some major traffic calming measures which will be completely in keeping with the green lane and because Vallee des Vaux is the big jewel in the crown of St Helier's green lanes, we want to make that a shining example of how you can treat a green lane."
A consultation is due to start to get islanders' views on the Sunday closure. Plans are set to include making allowances for people to still get access with cars to the supermarket at the bottom of the valley, but only from the south.
"I'd like to plan one event this year.
"The traffic calming measures (for next year) are not too expensive. We're definitely not putting policemen in or flower tubs everywhere, we've got more modern ideas." - John Baker, Roads Committee member.
The events are due to include trialling parts of the valley and then bringing in traffic-calming measures for the whole valley if they go well.
Mr. Baker also wants to speak to the National Trust of Jersey about hosting events in the valley when motor traffic is only allowed to residents.
"They've got a lot of land up there, the Jersey National Trust needs more awareness and money, so if for instance we have a 'National Trust Day' in the valley, it would be brilliant.
"We could get people doing guides looking at the birds, butterflies and trees and it would just be wonderful."

"Tropical nights" forecast for the Channel Islands
Les Amis nursing home on track to open this autumn
Candle-lit evening at St Brelade's Bay Beach to remember loved ones
How to have 'safe and enjoyable' Jersey beaches for summer
Appeal after woman grabbed by throat in nightclub
Essential work to begin on Springfield Stadium
Man who dug up cocaine in woods is jailed
Jersey and Guernsey included in UK-Gulf trade deal