Opening the Deep Woods and finding its entrance

The blocked stairs on the Eastern Road open only after one mines seal and the spell that comes with it.

The short answer

Break the Fire Seal in the Mines to learn Dragon’s Breath, then go to the northern stairs on the Eastern Road and cast the spell on the thick vines. The clearing scene permanently opens the route into the Deep Woods.

The actual unlock condition

The vines at the north end of The Eastern Road do not respond to an upgraded axe. They wait for Dragon's Breath, the spell awarded after Breaking The Fire Seal.

The Fire Seal is the third main seal in the Mines. Its altar asks for one of each item:

Offer all four and finish the seal scene. The seal guide explains the tablet chain and where the scroll fits into the wider mines story.

Clearing the Eastern Road entrance

Once Dragon's Breath is available, leave town to the east and follow The Eastern Road north. Cast the spell at the thorn-covered stairs. A short scene removes the vines and applies the change permanently.

The route is town, The Eastern Road, then The Deep Woods. Open the world map if you need the entrance in relation to the bridge and the rest of the road.

If the vines remain, check that the Fire Seal quest is complete rather than merely active. Owning the four items or reaching the seal floor does not award the spell by itself.

What becomes available inside

The Deep Woods has its own collection pools. The Deep Woods reference lists every linked item and the exact map facts, including:

nine bug species
five fish species and one active pond
one regional museum set in each of the four museum wings, with five items per set
connections north to The Dragonsworn Glade and south back to The Eastern Road

Use the location page as the checklist. It links each fish, bug and museum item to its full entry, which is more useful than copying a long static list into the route instructions here.

If the entrance still looks sealed

Work backward through these checks:

Confirm that Breaking The Fire Seal is completed.
Open the spell menu and verify that Dragon's Breath is available.
Go to the northern stairs on The Eastern Road, not a large stump elsewhere in the region.
Cast the spell directly at the thorny barrier and let the scene finish.

The Summit and The Deep Woods use different progression chains. Opening The Summit does not open this path; the Fire Seal does.