Heading out to an Iowa state park to enjoy some healthy, socially distanced outdoor activity over the weekend?Sunscreen? Check.Bug spray? CheckWater? Check.Passport?Wait, what?To encourage use of Iowa’s 71 state parks, the Iowa Department of Natural Resources and Iowa Tourism Office have kicked off a digital “passport” this spring.The response has been more than anticipated.“I think we always knew that there was great interest in the state parks, and with this being their centennial year, there would be enhanced interest in the parks,” said Jessica O’Riley of Travel Iowa.