Langtree held the first of a series of preview events to 'stress test' the Festival Gardens in Liverpool ahead of its opening 'in the next four to six weeks'.
The 90-acre park between Riverside Drive and Otterspool promenade next to the Mersey was due to open last year but was hit by delays following the collapse of main contractor Mayfield Construction. Langtree appointed Tolent Construction to finish the £4.5m project.
Local residents and councillors attended an invitation-only event on Saturday, which finished in a fireworks display to celebrate completion of work.
Stephen Barnes, development director of Langtree, said: "It's been a long road, with plenty of potholes along the way, but we are pleased and proud to say that we have now completed work on Festival Gardens.
"We felt it was important to mark the occasion properly and thank our neighbours for their consistent support and patience throughout the project. Each and every guest seemed genuinely impressed with what we've achieved, which is crucial as this park will be their legacy.
"This event was also essential to help us stress-test our work and ensure the park is robust enough for the people of the city to use for years to come.
"We have appointed the Land Trust to manage the site for us and there will be various other small events in the coming weeks to soft test the facilities before we fully open the park. If today's event is anything to go by, we should see Festival Gardens open to the public in a matter of weeks."
The site was home to the International Garden Festival for five months in 1984, but a series of failed ownership changes saw it fall into significant disrepair during the following 27 years.
Langtree plans to eventually build 1,374 new homes on 25 acres on the site of the former Festival Hall dome.
The park restoration was mainly funded by the North West Development Agency.