After less than two years at the helm of the new Knock Knock Children's Museum, Executive Director Peter Olson has resigned.

Museum officials announced on Wednesday afternoon that Olson's resignation becomes effective Sept. 30, saying they were surprised by the news but grateful for his service. Board Chairwoman Cate Heroman said Olson is leaving the museum to start his own consulting company in Minneapolis for people trying to open museums.

“It’s bittersweet; we’re really happy for him, that he can take what he’s learned at Knock Knock and bring it to national level with his consulting," Heroman said. "There were lots of tears shed this morning when we announced it to the staff.”

Heroman said Olson has left Knock Knock in a strong position, and the museum's director of finance and administration, Genny Nadler Thomas, will take over Olson's role on an interim basis. Olson oversaw the culmination of 14 years' worth of planning and fundraising to open the museum, and a successful first year with more than 218,000 visitors.

The visitor counts shattered the museum’s expectations for 189,000 visitors in year one. That made it among Baton Rouge’s most visited attractions; the Baton Rouge Zoo, for example, had 218,000 visitors in 2016.

Heroman likened their partnership to a “twin engine plane,” working together and helping each other. She said the Knock Knock board is creating a search committee for a permanent replacement and they will hire the same search firm, Chicago-based Kittleman, that helped them find Olson. She also encouraged locals to apply for the executive director position.

Olson could not immediately be reached Wednesday afternoon.

“It has been an honor for me to impact the children and families of Louisiana as Knock Knock’s inaugural executive director,” he said in a news release announcing his departure. “As I transition my career to the role of museum planning consultant, it’s a great feeling knowing that Knock Knock is poised for growth thanks to the amazing staff, volunteers, board of directors, community partners, and passionate donors.”

Follow Andrea Gallo on Twitter, @aegallo.​