A shot from inside the castle
Depending on which trail you take, this hike could be considered a Class 1/Easy (Bridle Trail) to a Class 3/Difficult (Castle Valley Trail, parts of the Squire's Lane Trail), but either way, the castle is a cool feature to check out! No need to hike any of the trails to get to the castle, as it sits just off the parking lot at the Squire's Castle Picnic Area & Trailhead (at River Road & Hayes Drive). If you follow any of the directions you find online, they will take you to the Strawberry Picnic Area, where you will need to hike either the Squire's Lane Trail (marked by brown salamander blazes) or the Bridle Trail (marked by yellow blazes with a person on horseback) to get to the castle - luckily, they also take you right by the Squire's Castle Picnic Area & Trailhead, so you can just turn in and park. There are restrooms located at this parking lot!
A look at the Squire's Lane Trail
Word of warning: the trails near the castle are not well marked, and we came across quite a few unexpected, unmarked intersections, which made navigation very difficult. In some cases, blazes were posted on the trees well above eye-level (as high as 8-9 feet up), and some were only arrows on a colored background, not the icon blazes denoting the trail. This can become quickly confusing for the novice hiker, and even we experienced hikers ended up wandering around the trails longer than we originally anticipated. We were able to take quite a few small children, who did well on the trails, even with some steep inclines, and the trails are wide enough and well groomed enough for tennis shoes, although boots are better for the Castle Valley Trail, Squire's Lane Trail, and Scenic Loop Trail. We also noted that the map at the Strawberry Picnic Area has the "you are here" spot marked incorrectly, which could cause hikers to turn the wrong way on the trail to get to the castle (you need to go east!).
The map on the information kiosk at the Squire's Castle Picnic Area & Trailhead
Here's a great map you can download before you go: https://www.clevelandmetroparks.com/getmedia/83e4a600-5e19-4cd8-8703-20ac1b60f070/north_chagrin.pdf.ashx?ext=.pdf