Taxi rank is standard in the UK (I think it is "stand" instead of "rank" in the US) and "taxi", "cab" and "taxi-cab" are all the same thing ("taxi" is a bit more formal, "cab" a bit more colloquial), so your sentence is fine, except that "at" would sound more natural than "in".
Because the words are so interchangeable, I would probably use them both to avoid such close repetition, so:
"It is easy to pick up a cab at the taxi rank" or "It is easy to pick up a taxi at the cab rank"