Hiking the Xiaoling Ancient Trail Hiking the Xiaoling Ancient Trail

The name “Xiaoling Ancient Trail” sounds unnatural in English, because our standard order of adjectives makes us want to put “ancient” before “Xiaoling”: “Ancient Xiaoling Trail” (or maybe “Old Xiaoling Trail”). I assume “Xiaoling Ancient Trail” is a direct translation of the Chinese name. If the reputable English guidebooks consistently use this name instead of Old Xiaoling Trail or some other variant, then you probably should too, even though it will sound “odd” to most native English speakers.

As you may know, I've spent a lot of time exploring the trails in Eastern China. As you may know, I've spent a lot of time exploring the trails in Eastern China.

not grammatically wrong, but I think the text would flow better if you put this sentence first. That way, it goes general to specific: I spent a lot of time generally exploring trails, and a few weeks ago I was on this specific trail.

As you may know, I've spent a lot of time exploring the trails in Eeastern China. As you may know, I've spent a lot of time exploring trails in eastern China.

I wouldn’t capitalize “eastern,” but I would capitalize East China, since it’s an official geographical term in China.

Perhaps the true ancient trail lies not only on a map, but also in the human heart. Perhaps the true ancient trail lies not only on a map, but also in the human heart.

“Not only on a map” seems a bit odd to me, since the trail also exists in real life (lying on the “land,” I suppose).

The paths walked by porters centuries ago still flow with a plainsimple warmth. The paths walked by porters centuries ago still flow with a simple warmth.

I like that word better here

The paths walked by porters centuries ago still flow with a plainsimple warmth. The paths walked by porters centuries ago still flow with a simple warmth.

“Simple” works better.

Nature's beauty is a gift of creation, but humanity's beauthe beauty of humanity is this:at even in this noisy, profit-driven era, there are still people willing to leave a door open, offer a handful of beans, and break off a branch of berries. Nature's beauty is a gift of creation, but the beauty of humanity is that even in this noisy, profit-driven era, there are still people willing to leave a door open, offer a handful of beans, and break off a branch of berries.

Nature's beauty is a gift of creation, but humanity's beauty is this: even in thisour noisy, profit-driven era, there are still people willing to leave a door open, offer a handful of beans, and break off a branch of berries. Nature's beauty is a gift of creation, but humanity's beauty is this: even in our noisy, profit-driven era, there are still people willing to leave a door open, offer a handful of beans, and break off a branch of berries.

Repeating “this” in such close succession grates on the ear. I’ve changed the second instance, but you could also change the first, as suggested by another corrector.

P.S.: P.S.:

There’s usually a colon after “PS”.