Translation:Nam freta prospiciens late riget arduus alto
Tmolus in adscensu, clivoque extensus utroque
Sardibus hinc, illinc parvis finitur Hypaepis.
Broadly surveying the seas, steep Tmolus stands up stiff in high ascending
and sloping [down] and spreading
is bounded on one side by Sardis and on the other by little Hypaepa.
The ablatives were difficult: late, alto, adscensu, clivo.
I read _late_ as modifying _prospiciens_, telling how, while reading alto as modifying adscensu.
I read _clivo_ as a noun, as joint object with _adscensu_ of the preposition _in_.
I Imagine a mountain tall and quite steep in its heights, but lower down sloping more gently outward until it reaches the two cities that bound it. Thus the center of the geographical description is a contrast between Tmolus up high, and Tmolus lower down.