Complex sentence: After 14 years he managed to escape from the pits, only to become lost in Dorthonion, there he was found by Beleg and helped to rescue Túrin Turambar and led him by way of Eithel Ivrin to Nargothrond.
Split into simpler sentences: After 14 years he managed to escape from the pits, only to become lost in Dorthonion. There he was found by Beleg and helped to rescue Túrin Turambar, and led him by way of Eithel Ivrin to Nargothrond.