Watch trains pass through the highest and longest tunnels on the former Pennsylvania Railroad Identified by railroad buffs as a œmust see stopover! The twin tunnels are the highest and longest tunnels on the former Pennsylvania Railroad. The first tunnel completed the railroad west and made the tunnels so valuable that they were guarded by the Pennsylvania Railroad Police during war times. Historic railroad museum with many RR and mining artifacts and video in the theater. Restored PRR caboose. Park open daily sunrise to sunset; staffed, noon-4 PM., Tues.-Sun. Extended hours for tour groups. Free.