谢谢版主回复，不是公共sidewalk。具体见内。

我们事故的这个trail由我们这儿的city/county管理，不在CBD，基本在郊区（我们这是小镇，我家住郊区，但是去downtown上班开车就8分钟），经过几个住宅小区的边缘，也没有明显的open/close时间。

又查了市政府有关trail的介绍网站（http://www.ci.rochester.mn.us/departments/park/trails/index.asp），我出事的trail叫“mayowood trail”，觉得我肯定是合法滑轮滑（inline skating）的。以下是描述：

Trails & You
The mission is to promote physical activity through the use of the city trail system. The city trails are a convenient way to include physical activities such as inline-skating, biking, running or walking. Even lifestyles changes, such as walking the dog, walking to work, biking leisurely or walking briskly can benefit you significantly.