Ellis Park in Danville, IN has a really nice, large gazebo.  It's big enough to have people under the gazebo while you get married in case it rains.  They have a really nice holiday light display in the park every year as well.   You can rent the gazebo for the day.  It's $50 for residents and $100 for non-residents.  Here is more info:  ​https://danvilleparks.recdesk.com/Community/Facility/Detail?facilityId=11

​My Fee to marry you in Danville is $180