The diminutive doors are front-hinged and you clamber in off the running board.
From the telegraph.co.uk
Later, we clamber off the bus straight into what appeared to be a staged protest.
From the guardian.co.uk
We clamber back aboard and slowly the great caterpillar of carriages pulls off.
From the smh.com.au
The small ground-dwelling frogs do not hop, but clamber over their mossy habitat.
From the smh.com.au
After our brief history lesson, we were free to clamber about inside the fort.
From the dispatch.com
Our tender pulls into a little beach near Bradleys Head and we clamber ashore.
From the stuff.co.nz
They clamber around an Abrams tank and squeeze into an amphibious assault vehicle.
From the jsonline.com
In an indoor gym, kids clamber up an artificial rock wall, suspended by harnesses.
From the statesman.com
We clamber down to the river below the village, Gerry and Rom leading the way.
From the guardian.co.uk
More examples
Climb awkwardly, as if by scrambling
An awkward climb; "reaching the crest was a real clamber"
Scrambling (also known as alpine scrambling) is a method of ascending rocky faces and ridges. It is an ambiguous term that lies somewhere between hillwalking and rock climbing. It is often distinguished from hillwalking by defining a scramble as a route where hands must be used in the ascent. ...
To climb something with some difficulty, or in a haphazard fashion
(clambering) Describes a plant that sprawls or climbs but lacks tendrils.
(Clambering) vine climbing without support of tendrils or twining stems ie. Vanilla
To attempt to extricate oneself from a particularly worrisome situation by clambering or deviously attempting to shift the emphasis elsewhere, for example by blaming your colleague when signing for an overpayment.