The legendary Liverpool manager Bill Shankly once famously said: "Some people think football is a matter of life and death, I assure you it's much more serious than that."
When it comes to certain club rivalries across the football world, this statement feels particularly apt.
Taking into account a range of factors, such as match atmosphere, fan rivalry and trophy counts, we highlight the top 10 fiercest derbies in world football today.
'The North West Derby'
The most famous Premier League fixture in the eyes of many, Manchester United and Liverpool are widely considered England's two biggest football institutions.
Located around 50km apart in the North West of England, the success of Man Utd and Liverpool is often measured in line with the fortunes of the other - with supporters of the Red Devils regularly singing of the club's 20 league title wins, one more than their Merseyside rivals.
Liverpool do hold the edge when it comes to European honours, however, with six Champions League crowns leaving Man Utd in their wake with two.
Two cities which are also long-standing economic and cultural rivals, the meetings of the two English football juggernauts at Old Trafford and Anfield each year always make for special occasions.
'De Klassieker'
Representing the two biggest cities in the Netherlands, Ajax of Amsterdam and Feyenoord of Rotterdam share one of the most passionate football rivalries in Europe.
Often competing directly against one another for domestic honours, Ajax are the Netherlands' most successful club having been crowned Dutch champions on 36 occasions, with Feyenoord lagging behind on 16 league titles.
A derby not only defined by the cultural differences of Amsterdam and Rotterdam, the two clubs are also traditionally divided by footballing philosophy - with Ajax deemed the artists and Feyenoord the more results-driven pragmatists.
It is often style versus substance whenever Ajax and Feyenoord clash in the Netherlands.
'Derby della Madonnina'
A rivalry which not only shares a city but also a stadium, the Derby della Madonnina between Milan and Inter represents one of Europe's most famous football rivalries.
The derby's name is a reference to the statue of the Virgin Mary on top of Milan's Duomo Cathedral, known as the Madonnina.
Like Man Utd and Liverpool, the two Milan clubs are very close in regards to major honours, with Inter revelling in a historic derby victory in 2023/24 which saw them clinch a 20th Scudetto, one more than Milan.
The Rossoneri hold the bragging rights when it comes to European success though, with Milan's seven Champions League titles clear of Inter on three.
Both housed at the stunning San Siro, Milan and Inter's histories are both defined by a desire to represent the city's number one football club.
'The Cairo Derby'
Arguably African club football's most intense rivalry, matches between Al Ahly and Zamalek reportedly draw in TV audiences of over 50 million in Egypt.
Al Ahly are Egypt's dominant club, winning 43 national league titles to Zamalek's 14, and 11 CAF Champions League crowns to their rivals' tally of five.
Egyptian football stops in its tracks whenever Al Ahly and Zamalek face off at the Cairo International Stadium, with this fixture one of the most anticipated days on the country's sporting calendar.
Al Ahly represent Egypt's republic-supporting nationalists, whilst Zamalek are a pro-royalist club.
'The Eternal Derby'
Since the establishment of the Serbian SuperLiga in 2006, only two clubs have been crowned champions - Red Star Belgrade on 10 occasions and Partizan Belgrade eight times.
The two neighbours share an intense rivalry steeped in socio-political history, with Red Star long recognised as the team of the interior ministry and Partizan the side of the Yugoslav Army.
Red Star v Partizan derby matches today are vociferous affairs, with ultras on either side attempting to outdo each other with tifo displays and pyrotechnics.
'Derby della Capitale'
Arguably the fiercest fixture in the Serie A calendar, there is certainly no love lost between the supporters of Rome's two football clubs - Roma and Lazio.
Sharing the same home of the Stadio Olimpico in Italy's capital, like many derby matches the rivalry between Roma and Lazio is steeped in socio-political tensions, with Roma characterised as the club of the working class people and Lazio recognised as the club of the rich.
Prior to derby matches, Roma supporters congregate in the city's Curva Sud with Lazio fans based at the Curva Nord, adding to the sense of anticipation before the 90 minutes at the Stadio Olimpico.
'El Clasico'
Although the two teams don't share the same city, the rivalry between Real Madrid and Barcelona remains one of the most iconic in world football.
Two of the biggest football clubs on the planet who have given homes to some of the sport's most legendary players, namely Cristiano Ronaldo and Lionel Messi in the 21st century, this fixture is regularly watched by over 700 million people around the world.
Real and Barca both share the same ambition to conquer both Spain and Europe, although it is Los Blancos who come out on top on both fronts - with 36 La Liga titles and 15 Champions Leagues to the Catalans' respective tallies of 27 and five.
This rivalry not only regularly showcases the finest footballers in the world, it reflects the two polarising identities of Spain's capital of Madrid and the region of Catalonia.
'The Intercontinental Derby'
Turkish football fans are world renowned for their uniquely passionate support, with Istanbul rivals Galatasaray and Fenerbahce the country's two most successful clubs.
Galatasaray, founded by students, are based on the European side of Istanbul, whilst Fenerbahce, regarded as the people's club, have their roots in the Turkish capital's Asian region.
Derby matches between the pair are played in cauldron-like atmospheres full of colour, pyrotechnics and intense hostility between rival fans.
This rivalry gains an added edge in the fact the two teams are regularly competing at the top of the Turkish Super Lig, with Fenerbahce record 28-time national champions and Galatasaray league winners on 25 occasions.
'The Old Firm Derby'
One of the oldest club rivalries in the world of football, first taking place in 1888, Celtic v Rangers is also one of the most bitter derby matches in the sport.
Again identity politics is at the heart of this rivalry, with Celtic founded by Irish Catholics and Rangers recognised as a Protestant, Unionist club.
The two teams dominate the Scottish football landscape and have competed directly against each other for silverware for the majority of their respective histories, with Rangers' tally of 55 league titles two ahead of Celtic's total of 53.
It has been almost 40 years since a club other than Celtic or Rangers won the Scottish league title, with Old Firm derbies typically critical in determining which half of the Glasgow divide are crowned champions.
'Superclasico'
A bucket list football fixture to attend for fans of the sport across the world, the rivalry shared by Buenos Aires neighbours Boca Juniors and River Plate is truly unique.
Whether it be at Boca's La Bombonera or River's El Monumental, the supporters of two of South America's biggest football institutions deliver an epic atmosphere and spectacle defined by an intense disliking of one another.
Traditionally, Boca are the club of the working classes, with River representing a suburban middle class.
River Plate have won the most Argentine league titles, with 38 to Boca Juniors' 35, but Boca have more Copa Libertadores trophies (six) than their Buenos Aires adversaries River (four).