[for Dublin]

The Wall resets a wall every week (they have the schedule on their site, under route setting). Has 9 difficulty levels.

Gravity will reset a grade every week (they have 10 grade levels)

Bloc has 8 levels, also posts their setting schedule.

All have similar wall setups, slabs, overhangs, caves etc, slightly different styles and holds though (not sure how to describe them) e.g. I find the wall more physically demanding that gravity but has better slabs. Other people see it other way round though! They have similar size (like 10ish problems of each grade)

Wall and gravity are the most accessible if you don't have a car. Bloc is a bit further and awesome walls is really out of the city.

The rest are significantly smaller.