Campaigners are marching through a Teesside town to protest at controversial development plans.
The Forum was opened in 1967 by the Queen
Billingham's Forum Theatre would be demolished to make way for a supermarket as part of plans to regenerate the town centre.
Stockton Council made the decision in May, saying the site must be sold off to help fund another leisure complex nearby.
Protesters are marching through Billingham town centre on Saturday.
The regeneration plans involve selling the Forum site and using the cash to help fund a new complex in nearby John Whitehead Park.
The new centre would house an ice rink, swimming pool, fitness centre, library and health facilities.
Campaigners have pledged to fight the demolition of the theatre, which was opened by the Queen in October 1967.
But Stockton Council said it was the best way forward to regenerate the town.