Impossible to traverse.

That cannot be passed through or travelled across; = impassable, adj. 1. Formerly also as adv. (obsolete rare). Cf. unpassible, adj.2

Impassable. Cf. passageable, adj.1

That cannot be passed, impassable. In early use chiefly poetic and literary.

That cannot be passed again.

That cannot be passed through or travelled across; = unpassable, adj. 1.

(un-, prefix1 affix 1b.)

That cannot be put to use or practically dealt with; unmanageable, intractable, unserviceable. Of roads, districts, etc.: Incapable of being used…

That cannot be entered or passed through; impassable, impenetrable. Also with to.

(un-, prefix1 affix 1b.)

That cannot be passed along, through, or across; impossible to traverse or travel through.

Hemmed in, limited, or hindered from movement by surrounding land.

Not allowing the passage of water, air, light, etc.; not able to be passed through or penetrated; impenetrable, impermeable. Also with to, against.

That cannot be traversed or crossed.

That cannot be ridden; that cannot be traversed by riding; not rideable.

Unavailable for transit.

(un-, prefix1 affix 1b.)

(un-, prefix1 affix 1b.)