Turkey Ridge is a rock bottom quarry near Janesville, Iowa. It is owned by the county and you must have permission (acquired by signing a waiver and donating to the upkeep of the quarry) to use this site. There is also a training platform, tube swim-through, sunken statue, and a few other points of interest.
Big Blue is a quarry located in Lester Milligan Park in Mason City Iowa. The quarry is on the South West side of town approximately 2 miles North of IA-27. There are several places to park for an easy shore entry.