The Park Avenue Armory in the Upper East Side has morphed into a funhouse for this weekend, with a 50-feet-tall ferris wheel and other carnival rides.

The 130-year-old building on Park between 66th and 67th Streets, which is also known as the Seventh Regiment Armory, is hosting the four-day event, which will also feature circus performers on stilts and contortionists.

The carnival celebrates completion of the first phase of a $200 million renovation. Four years ago, a nonprofit leased the armory from the state to use as an arts and performance space.

"One of our board members said, wouldn't it be great to have a county fair in the drill hall? We all went, 'I don't know about that.' Anyway, we actually did do it," said Park Armory President Rebecca Robertson. "What's really different about this space from, say, a conventional theater is that artists can do just amazing things and create their own environment."

Josh Hickey of Hickey Shields Design was able to do just that when he designed the carnival's look.

"We said, okay, it's cool to put a ferris wheel inside, it's cool to put games inside the building, but it's not enough," said Hickey. "We wanted to really make people feel like they were walking onto a Broadway stage where there was like a big show about a carnival. Really have almost a theater effect."

The carnival runs through Monday. Admission is free for children under 13 and armory members, and adults can get in for $5, plus the costs of the rides.

For more information, visit ArmoryOnPark.org.