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Changes to Our Grading

Written by Kornelija Langley - Route Setting Manager

We have recalibrated our bouldering grades! This means that the difficulty of the sets has not changed, but the grades we give the problems are different. Even the circuits are staying the same difficulty, although the tags will show changed grades.


The process behind this decision was a lot more involved than may be immediately apparent. Read on if you are curious about different grading systems, want to know why we use V grades and understand the reasons behind the recent changes. 

Grading systems and why we use V grades...

Most of you who climbed outside at different areas and used different grading systems will know that there is no perfect solution to grading. Commonly used bouldering grading systems are V Scale, which originated in Hueco tanks in the USA, and Font grades, which, as name suggest, is used in Fontainebleau forest in France. In order to be able to compare these scales’ suitability for the Castle’s indoor bouldering we first have to get a little technical…

The Font grades provide us with 48 grades along the scale of difficulty, V Grade (currently used at the Castle) has 21 grades for the same range, while British Tech (previously used at the Castle) only 10! What’s more it is not as simple as Font system having 5 grades for every 1 grade of British Tech. Some scales provide more grades in easier range while other in the harder range (see table below), i.e. they are skewed at different ends of difficulty spectrum. For example, the Font grading system offers a lot more grades in the easy range compared to V Grade. It has 18 grades (1a, 1a+, 1b, 1b+, 1c …4a) which could all fall under 1 grade in V grading system - VB! In reality it is near impossible to tell the difference between so many difficulty levels of easy climbs and those of you who climbed beginner circuits in Font would have witnessed just that – extreme inaccuracies in easy grading. Some try to fix this by removing the letters for grades up to 6a and simply grading them as 1, 1+, 2, 2+, 3…

V Grade, on the other hand, comes into the easy spectrum arguably too late (it technically starts at V0), leaving us with only a couple grades to get to V2! To solve this problem grades such as VB (which stands for ‘beginner’ or ‘basic’), V0- and V0+ came into use. Font and V systems begin to match up grade-for-grade quite nicely after 7a or V6, although V Grade does not offer an equivalent to Font 7b+, which is how V8+ was introduced to a system that otherwise only used simple numbers to determine the difficulty (…V6, V7, V8, V8+, V9, V10…). 

So both systems have their flaws with less-than-elegant attempts to fix them and there is no universal difficulty range within a single grade. The reason we use V grade at the Castle is because it is simpler and it has fewer grades overall, which avoids the need for arguing whether something is 6b or 6b+ as they both fall under V4. 


So why are we recalibrating our V Scale?

First of all you may have noticed that we have been only giving problems tags up to V8 (with occasional exception) where in reality the difficulty of Castle’s problems go up to V10-11. This made the top end grades very bunched with our V6 covering anything from V6 to V9. The reason to have V8 as cut off point was that the pressure on route setters to grade super hard problems accurately is unfair as they have such short time to test them. Hard outdoor blocs would be ‘projected’ and completed before given a grade (this is not the case in indoor setting where setters may only do individual moves to assess the difficulty without having time to do the link). Also outdoors the grade may be changed and refined by future ascensionists. So bunching all the hard grades made sense especially since anyone that climbs the extremely hard blocs at the Castle will be experienced and will know their own level and will be able to assess the difficulty of the bloc.

This strategy meant that our V5s, V6s, V7s, and V8s got quite detached from the actual difficultly of these grades outdoors. With more and more people climbing these grades at the Castle and our setters getting stronger and stronger it makes sense to bring them closer to their outdoor difficulty which is why we are recalibrating.

We are doing this by introducing V9 and V10 tags (for what is currently graded V8 and V8+) into our regular sets and since the actual difficulty of the set is staying the same this will have a ripple effect throughout the easier grades. We are also simplifying our grading by no longer using V0- because it has never been an easily distinguishable grade, as useful as an extra ladder rung on a well-spaced ladder – it was often skipped.

Does this mean that all our grades will match up perfectly to outdoor grades? Not really. Besides the problems with easy range grading outdoors, outside grades can be very varied dependent on area and on when the problems were established (older problems tend to have stiffer grades because as sport of bouldering evolved each new hardest ascent was simply given the next hardest grade and even though eventually it may have turned out that there could be 2 or 3 distinguishable in-between grades, the original grades often stuck). So while we will try to get our grading closer to what you might find outside the main goal remains to have a neat grading system with well-spaced grades that will serve as a good guide to Castle’s climbers.


Bouldering Grades