The short answer for a Harlequin rabbit
A Harlequin rabbit suits two depths rather than one: roughly an inch of bedding across the main floor, and four to six inches of loose bedding in a dedicated nest or dig corner. Harlequins are medium, solidly built rabbits with a strong urge to shove material around with their nose and front paws, but they are rearrangers rather than true tunnel builders. Giving the whole pen a deep layer wastes bedding and buries hay racks, while giving a Harlequin nowhere deep to dig leaves that instinct with nowhere to go except the litter corner.
Why a Harlequin rearranges more than it burrows
A Harlequin rabbit scratches, pushes, and piles bedding into a chosen hollow, then flops beside or partly inside it. That nesting behaviour is about shaping a comfortable, scent-familiar resting place, not about holding up a tunnel roof. Deep loose bedding spread wall to wall collapses under a rabbit of this size anyway, so the depth only really works where the Harlequin can work it against a wall, a box side, or a shelter. Concentrating depth in one protected corner also keeps the eating and toileting areas cleaner, which matters because rabbits graze hay close to the ground and will ignore bedding-soiled hay.
Setting up the two depths in a Harlequin pen
Set up a Harlequin pen by laying about an inch of unscented paper-based bedding or a washable fleece liner over the main floor, firm enough that this rabbit can hop without skating. In the quietest corner, place a high-sided box or tray and fill it with four to six inches of loose paper bedding, then pull a generous handful of soft hay across the top. The hay cap invites foraging as well as digging, and it keeps the loose layer from being flung out in the first hour. Position the dig box away from the water bowl, because a digging Harlequin throws material backwards with real force. If your rabbit is a doe who begins pulling fur and carrying hay in her mouth, deepen that same corner toward six inches so she can build a proper nest hollow, and leave her arrangement alone rather than tidying it flat.
Keeping the deep corner fresh for a Harlequin
A Harlequin dig corner stays pleasant if you lift out damp or soiled handfuls daily and top the depth back up, instead of stripping the whole box on a schedule. Rabbits return to a corner that still smells faintly like themselves, so spot-cleaning preserves the attraction while a full replacement can make the box feel new and ignored for a day. Check that the deep layer stays dry right to the bottom, because a rabbit resting in a damp hollow can develop sore skin on the feet and belly. Rotate a second material into the box occasionally, such as clean straw over paper bedding, and note which combination your Harlequin actually digs in rather than simply sitting on.
Signs the depth is wrong for this rabbit
A Harlequin rabbit whose dig box stands untouched while the litter tray gets excavated is telling you the deep corner is in the wrong place or holds the wrong material. Move the box to where the digging already happens before changing anything else. Bedding piled against the pen door each morning usually means the main floor layer is too deep and is being bulldozed, so thin that layer down. Contact a veterinarian if a Harlequin stops eating, produces far fewer droppings, or develops red, sore hocks, because appetite and foot changes in a rabbit need prompt attention rather than another bedding experiment. Note the set-up that finally works, including both depths and the box position, on the rabbit's profile so a holiday helper rebuilds it identically. KinsLe Family Sharing keeps that Harlequin bedding layout visible to every family member who helps, so the deep corner survives a change of cleaner.