Distance from downtown Mankato: Roughly 5 miles.
Route I took: There are two different routes I've taken to get to the park. Here is the route I initially took when I first moved to Mankato and knew little about its bike trail systems. I mostly just followed Highway 169/60 to the turnoff point and found the park from there. Here is the route I took when I visited the park earlier this summer. This was after I found out that the South Route Bike Trail crossed County Road 60 into the park area. It mostly just follows the Red Jacket Trail to its intersecting point of the South Route Trail, when you then take it all the way to the park.
General ease/challenge of ride: Regardless of which route you take, you're going to encounter some hills along the way. The 169/60 route generally has a more gradual slope to its hills, whereas South Route's hills are consdierably steeper, particularly coming out of the Blue Earth River valley. I would consider the 169/60 route to be easier because the hill climb is easier and the distance is shorter (4.5 miles vs. 6.7 miles). However, the tradeoff is in the route's safety.
Safety of the ride: Depending on which route you take, the general safety of the ride is
hugely different. The South Route way is entirely on bike trails and crosses very few busy intersections (Highway 66 is probably the busiest crossing, and I don't recall traffic ever being backed up there). In contrast, the more direct 169/60 route rides along two busy streets (Riverfront Drive, then the highway) the entire way. Riverfront has a walkway and the highway has a wide shoulder, but the sound of vehicles zipping past is a precarious one for any cyclist. It all boils down to what you value more: Trip speed or safety.
Appeal of the destination: Minneopa is one of the oldest state parks in Minnesota, so if you're into camping and hiking, you're sure to find a lot of it there. The park has an abundance of campgrounds and the hiking trails along the Minnesota River at Minneopa offer a lot of scenic views of the river valley. For those with a pension for history, the Seppman Mill at the west end of the park is an intriguing find. According to the Greater Mankato Visitors Bureau, the mill was built in the 1860's by German immigrant Louis Seppman and powered by wind to process grains until the 1890's. The mill is listed on the National Historical Register as a historical sight. I didn't know about the mill during my initial visit to the park, but later found out about it after glancing at a park map and visited the sight earlier this summer.
Of course, you can't talk about Minneopa without mentioning the falls area. It simply doesn't get any better than this for waterfalls in the Southern Minnesota area. There's a nicely maintained picnic area at the top of the falls and hiking trails to lead you down to the base of it. The falls don't have much for swimming areas (I wouldn't recommend it, too rocky), but it does offer a lot of good viewpoints to take in its splendor. For the adventurous and dangerous type (which I'll confess to being on occasion), there are a few very accessible caves to climb into along bluffs lining the waterfalls. I recall the one I climbed into had enough "this person *hearts* this person" scrawlings in it to be nicknamed the "tunnel of love."
Another upside about biking to Minneopa instead of driving: You don't have to pay for parking to view the falls.
So, Sparky needed to go out but it was Bennie who came down to the bedroom and woke me on her behalf. Animals are so much more intelligent than some people give them credit for. 
How is it that a 2nd grade, 45 pound, petite 7 year old girl scout can belch and fart louder and smellier then a sailor.
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