The Welsh Eden — not to be confused with the Cumbrian river of the same name — is a small Snowdonia tributary of the Mawddach, running mostly southerly from Trawsfynydd down to Y Ganllwyd. Wild brown trout in spate-river water, three short Passport beats (Upper, Middle, Lower) at a tenner a day each. The kind of small water where a six-foot rod and a willingness to crawl are worth more than any amount of gear. Sea trout work up from the Mawddach but the Eden itself is a brown-trout river.

• Slate shale snowdonia