The former swimming pool and music venue in Southsea, run by BH Live, won the cash injection from Portsmouth City Council after high maintenance costs saw the authority seek a new use.
Now the Exploria children’s play and bounce facility boasts ‘three massive adventure worlds’.
It comprises the bounce zone with an open area, ninja course and parkour elements.
Ancient worlds are depicted in the junior soft play zone, with climbs, slippery slides and ball pits.
Toddlers and babies can enjoy themselves in safety from older children in their own area.
The upstairs plaza gig space in the centre has been converted into a brand new gym, with the existing gym regenerated into specialist fitness studios.
A one-hour session with access to the junior zone and baby and toddler zones costs £3.95 per person.
A one-hour session for children five and older costs £10.95 - while a family ticket costs £36 for two adults and two children.