The phrase "a tall rail" is correct and usable in written English.
It can be used to describe a rail that has a significant height, often in contexts related to construction, fencing, or design.
Example: "The garden was enclosed by a tall rail that provided both security and an aesthetic appeal."
Alternatives: "a high rail" or "an elevated rail".
A tall, rail-thin man in a Navy seaman's uniform was escorted onto the stage.
The newsroom got its first sustained look at Thomson, a tall, rail-thin, slightly stooped man with a high forehead, short hair that hugged his scalp, and half glasses pushed down on his long nose.
FUGNIDO, Ethiopia — At 10 p.m. in a sweltering refugee camp here in western Ethiopia, a group of foreigners was making its way past thatch-roofed huts when a tall, rail-thin man approached a silver-haired American and took hold of his hands.
Shola was a teenager -- six-feet tall, rail thin and heartbreakingly gorgeous.
Garnett entered the league seven feet tall, rail thin, and lethally bouncy in 1995, when the platonic ideal of a player with so much size was the burlier, back-to-the-basket Shaquille O'Neal.
The writer met a hard core named Robert Lee Hodge who looked as though he had stepped from a Civil War tintype: tall, rail-thin, with a long, pointed beard and a frayed and filthy uniform.
There is an approximately factual scene from 1962 in "Isn't She Great" in which Susann marches over to what she called her "wishing hill" in Central Park and, glaring up through the branches of a tall tree, rails at God.
A physically imposing man – well over 6ft tall, rail-thin, with a long bushy beard – he was best known internationally for having twice been arrested for his political reporting.
He formed AIP in 1954 with a borrowed $3,000 and tall, rail-thin James H. Nicholson as his partner.
At over six feet tall, rail-thin, and with a protruding nose and strange clothes, he was described by one observer as "a character out of a fairy tail [sic]… who would have fitted nicely in elf's clothes".
Today Walmart announced it has acquired ModCloth, a womenswear retailer that focuses on a younger, progressive demographic and a healthier range of sizes beyond the too-often-emphasized tall, rail-thin look.
