Spanish has given us several words to name features of our landscape. We start with one rooted in a lovely metaphor.

bolson – a flat arid valley surrounded by mountains (can drain into a shallow central lake)
[Spanish bolsa, 'purse, pouch'; ultimately traces back to Greek 'wineskin']

The army had made its bivouac at a bolson fed by seeping springs and bordered by green marsh grass …
– Stephen Harrigan, The Gates of the Alamo

… extending from southern Oregon to western Texas, the [Southern Arizona] Basin and Range is an immense … region of north-south-trending, faulted mountains separated by wide, dry bolsons (basins of interior drainage).
– Randall J. Schaetzl, Sharon Anderson, Soils: Genesis and Geomorphology

Bonus word:
bivouac – a temporary camp without tents or cover (verb: to stay in such a camp)

Here is another Spanish-loanward rooted in a metaphor.

sierra – a range of mountains having an irregular or jagged profile
[From from Spanish for 'saw'. The Latin root also gives us 'serrated'.]

Mountains along the California/Nevada border are often called the Sierra Mountains (rather than 'the Sierras'). Technically that's improper, since 'sierra' implies mountains.

The next town they entered was two days deeper into the sierras. They never knew what it was called. A collection of mud huts pitched on the naked plateau.
– Cormac Mccarthy, Blood Meridian: Or the Evening Redness in the West

llano – an open grassy plain, treeless or nearly so

In Venezuela the fault-line ran between the mercantile and landowningh elite of Caracas and the Indian peasants … who ranged freely with their animals over the llanos – the grasslands of the interior – and saw the crown as their protector agains the growing menace of encroachment by the Caracas landowners.
– John H. Elliott, Empires of the Atlantic World: Britain and Spain in America 1492-1830

paramo – a high, bleak plateau or district, with stunted trees, and cold, damp atmosphere, as in the Andes

At its altitudinal extreme, cloud forest may be stunted, becoming a bizarre elfin forest of short, gnarled … trees. Higher still on some mountains is treeless paramo, an alpine shrubland, or puna, an alpine grassland. – John Kricher, A Neotropical Companion

Bonus word:
puna – 1. a high bleak plateau in the Peruvian Andes 2. difficulty of breathing due to thin atmosphere; mountain sickness

Arid, cold, and in general, covered by short coarse grass, the puna has, nevertheless, long supported an Native American population. The icy wind sweeping the mineral-rich plateaus is also called puna. – Columbia Encyclopedia

cuesta – a ridge with a gentle slope on one side and a cliff on the other; a gentle upward slope ending in a steep drop
[Spanish, from Latin costa, side]

… the land surface is underlaid by strata that have been slghtly warped into the form of a stack of nested saucers. Erosion has exposed the edges of the saucers to form "cuestas," and it is in those exposures that fossils can be collected.
– Arthur N. Strahler, Science and Earth History: The Evolution/Creation Controversy

arroyo – a deep and usually dry gully cut by an intermittent stream

Over hogbacks, down into wooded watersheds, arroyos that carry the snowmelt down to the big river. Only a trickle now.
– Summer Wood, Arroyo: A Novel

Bonus word:
hogback – a long steep hill or mountain ridge

Overcoming my fear of interrupting your train of thought, Wordcrafter, I'd like to offer buckaroo, which obviously evolved from Spanish vaca (cow) and vaquero (cowherd)

Absolutely no problem, JT. By the way, vaquero has also come into English as a recognized word.

If you have $20 million to spend, today's post will give you a shopping tip.

cay – a small, low island of coral or sand
[Sp. cayo shoal, rock, barrier-reef]
Key (as in the Florida 'keys') is a variant of the same word.

A private island can be what one real estate specialist calls "the ultimate trophy" … Big price gaps do exist between areas that have been frequented by the wealthy for decades and those that have not. … there are emerging areas like the cay-dotted coasts of Belize, Honduras and Nicaragua. "The absolute cheapest land in the Caribbean is in Nicaragua, followed by Honduras and Belize," Morrison said.
– International Herald Tribune, France, May 25, 2006

Actually, a hogback describes a specific type of landform caused by tilting of rocks with a resistant layer. The ridge has a dip-slope (top of the resistant layer) and a steeper slope on the opposite side, where the underlying more easily eroded rocks are exposed. The ridge often has a sharp crest of the harder rock, which resembles the hair that sticks up on a wild hog's back. In fact, the name for a landform similar to a hogback (but with shallower dip) is another land-word loanword "cuesta" meaning hill in Spanish.

For a complete definition see http://en.wikipedia.org/wiki/Dip_slope

quote:

Originally posted by wordcrafter:
arroyo – a deep and usually dry gully cut by an intermittent stream

Over hogbacks, down into wooded watersheds, arroyos that carry the snowmelt down to the big river. Only a trickle now.
– Summer Wood, Arroyo: A Novel

Bonus word:
hogback – a long steep hill or mountain ridge