They are separated by history, civic rivalry and the rolling hills of the Pennines.
But two years ago, in the aftermath of the Manchester Arena bombing, the white and red rose counties of Yorkshire and Lancashire came together as one.
Vigils were held in many parts of Yorkshire on the night that followed the outrage, with Leeds Minster playing host to a special service that was attended by faith leaders and council chiefs.
The Bishop of Leeds, the Right Rev Nick Baines, told the congregation: "We find ourselves looking for some words, for a vocabulary, to help shape how we think and how we respond.
"The desire of terrorism is to terrorise and the resistance to terrorism is to refuse to be terrified. It’s partly a choice, we can choose not to be terrified."
In Sheffield, hundreds of people gathered in the city's Peace Gardens to remember and show solidarity with Manchester's fallen.
And, on the Sunday after the bombing, a prayer vigil took place in Wakefield Cathedral.
Many of those present had made their way to the cathedral in a procession from the Ghausia Masjid mosque on Duke of York Street in the city centre.
That same weekend, armed police were on the streets of Leeds, aiming to provide reassurance for people heading to major events such as the Slam Dunk music festival and a gig by The Specials in Millennium Square.
Across town, Adam Ant took to the stage at the city's First Direct Arena, where earlier in the week staff had sent "thoughts and prayers" to their heartbroken counterparts at Manchester Arena.
A full-scale review of security was carried out at Leeds's arena – and similar venues across the country – in the wake of the bombing.
A wider safety cordon now operates in Leeds as crowds arrive for events, with only ticket-holders being allowed through to the security arches and bag check areas directly outside the arena.
Backpacks and large bags are banned from the venue while sniffer dogs are also used ahead of some events to detect drugs or explosives.
Speaking in December last year about the changes that were made, the arena's head of operations, Martin McInulty, said: "The comment I heard most often then tended to be, I know this is going to take a bitmore time, but I’m happy to queue if we know we’re going to be safe’. The feedback certainly at that time was really positive."