The Hopkinton Trails Club will host a guided walk at Highland Park/Saddle Hill on Saturday, Dec. 13, at 10 a.m. This trail system, tucked in and around a residential neighborhood, offers level paths, climbs, views, forests and more. The route is a nearly three-mile loop, following the Greenwood, Sands, Saddle Hill and Betty Fitzpatrick trails. It should take about 2 1/2 hours, with stops to enjoy vistas. Participants will meet at the Emerald Hills East soccer field parking lot (across from 48 Greenwood Road). For more information, visit hopkintontrailsclub.com.