The Thun Trail (pronounced tune) is part of the Schuylkill River Trail System. Large railroad bridges, built in 1918, provide impressive views of the Schuylkill River and the surrounding hills. Paralleling Routes 422 and 724, this section of the Schuylkill River Trail offers an alternate route for commuters and beautiful views for those seeking leisure activities. It is just over 18 miles long. Currently there are two developed segments of trail connected by an on-road route. The Western end between Reading and Gibraltar is 5.8 miles long. Then there is four miles of on road route and then another developed trail segment 8.9 miles long.