To the south of the island is Jeondeungsa (전등사), a pretty temple dating from the fourth century – when Buddhism was just taking root on the peninsula – making it one of the oldest temples in the country. It was also the venue for the creation of the famed Tripitaka Koreana, eighty-thousand-plus blocks of carved Buddhist doctrine which now reside in Haeinsa temple near Daegu. To reach the temple, take one of the half-hourly buses bound for Onsu-ri. About 5km west of Onsu is Manisan (마니산), the main peak of the island, which affords wonderful views of the surrounding islands.
Studding Ganghwado’s east coast are three fortresses – Gwangseongbo (광성보), Deokjinjin (덕지진) and Chojijin (초지진) – which are best seen by making use of the bicycle lanes that run alongside the main road; otherwise, buses run every hour or so. Gwangseongbo (daily 9am–6pm) is the northernmost and most interesting of the three, and dates from the mid-seventeenth century; its strategic importance will be obvious to all visitors, as it peers out over the channel that separates Ganghwado from the mainland.