You'd be hard pressed to find the time, or money, to read all of the books to have featured Batman. With an entire utility belt's worth of classics, not to mention the comics focusing on his allies, there are plenty of well-regarded options to choose from.
Yet, there is one bat-book which really does deserve a bit more consideration, namely Brian Azzarello and Matteo Casali's Batman: Europa.
The mini-series was originally announced in 2004, but, instead of releasing on its intended date, the comic faced a rather tumultuous period of development. It was years after the original release window, in 2011, when the book was announced yet again, but this didn't prove to be the end, with the comic actually being released across 2015 and 2016, 11 years after its initial announcement.
During this time, the Bat had gone through some pretty major events in DC's main universe, having died, gained a son and had all of his books rebooted as a part of the New 52. This was perhaps why this bat-book was so overlooked, but those who have read Europa will be all too aware of its quality, and why it being so overlooked is particularly frustrating.
Visually unique, and with a premise that ties together Batman's real-life origins with his mythos, Europa isn't a book to be neglected...