Aobanomori Park offers a short but very pretty run in Chiba. There are attractive paths through Western & Japanese gardens with cherry & plum blossoms. There’s also a natural history museum. A loop of the park’s paths is ~3.5 km, but it’s possible to make this a ~5 km route by adding the other park paths. And, there’s a running track at the western end!

Longer Run: Combine with Inohara Park, a small but pretty park known for its centuries-old castle with a restored tower and spring blossoms. Use Park Kita St. (northwest end of park), and run for 1.2 km to Inohara Park (not that pleasant, but runnable). There are 1-2 km of paths around Inohara Park.