Types of shelters chosen by wild Red-foot Tortoises include…

• Animal burrows- such as those of the armadillo and agouti.
• Debris piles- clumps of fallen branches and leaves. 
• Treefalls- the space and loose soil made by an uprooted tree.
• Dense vegetation- under thick leaves, vines, branches, etc.
• ‘Open
  shelters’- where the tortoise is wedged into or nestled down in the
  vegetation or debris, but still rather exposed, especially at their
  backs. 

Most
selected shelters are slightly cooler than the air temps, often 12c/10f cooler, snug, and
humid. Interestingly, Red-foots are often found in flooded shelters-
bodies immersed and just their heads above the water.This is a handy
skill in the high rainfall habitats they prefer.

Red-foots often enter a sheltered location and push forward until they are securely
wedged, making it hard for predators to pull them out. Younger
Red-foots seem to like snuggling down in the soil as well. [Moscovitz 1985]

Basic design issues
Based on the above issues, shelters or hides we offer should be…

• Snug.
  The shelters should be designed to let the tortoise wedge itself in-
  jam in between items, snuggle up under a low roof, nestle into softer
  material, etc.
• Cooler.
  While the average habitat temp should be about 30c/85f, the shelter
  temps can be 27c/80f or even a little cooler. Note- all things being equal- lowering
  temps will boost humidity.
• Large. The tortoise should be able to feel like nothing can see it where it is. The further it can get out of sight, the better.
• Dark.
  Many shelter choices allow lots of light during the day, but there is
  little light in the wild at night. Allow your tortoises a true dark
  night for the best rest. Since they can see colors, using black, blue, or red lights at night may not be the best choice.
• Safe. Some
  shelter designs or materials may be risky. Overly damp or contaminated
  substrate or nesting material may cause shell rot. Some designs may
  inadvertently trap the tortoise inside, etc. Shelters should above all
  be safe for the tortoise.

Traditional hides used for other
reptiles- basically boxes with
holes in the sides- may not be the best hides for tortoises. The large
open space in the traditional hide does not offer the opportunities to
wedge in. Most keepers find that when offered a choice, their Red-foots
will usually select a shelter that meets the above criteria.

The ‘bark lean-to’ hide is an improvement over the ‘box with a hole’ hide, but it can be made even better in many ways:

• Using
  bark instead of plywood or lumber offers a more natural look and feel,
  and the back side of the bark naturally holds more moisture, as well as
  having a ‘rough but soft’ texture that aids in offering the feeling of
  snugness.
• Using a filler that is light and fluffy, but not
  acidic (moss, for example, is acidic) allows snuggling as well, and can
  help with humidity when it is damp but not dripping wet. Shredded bark, leaf litter, paper toweling, etc. can be used.
• Humidity can be improved by adding sheets of moss or toweling on the bark or over the back or upright
  wall and keeping it moist. It also adds to the snugness, and darkness.
• We
  want to aim for a slightly cool hide, but it should never be chilly or
  clammy. If it is necessary to heat the hide, cables, tapes, mats or
  pads under the substrate or habitat would be the best options as long
  as they do not overheat the smallish space.
• Offering multiple hides offers the tortoises choices.
• Smaller tortoises often seem
  to like a hides made of several chunks wood loosely piled up so
  they can select the openings and snugness.

Moist root shelter
Editha Kruger
made a great hide by growing a layer of grasses and forage plants over an engineered
‘cave’. The end result provides a cool, moist, dark, snug hide that also
provides a place to explore, foods to graze on, and more. She also felt that the combination of snugness with
moistness helped produce smooth, solid shells for her Mediterranean
tortoises. The basic plan is simple:

1. Make or find a tray
   a few inches (about 10cm) deep the size you need the shelter to be.
   Usually, it would be longer than the width of the habitat, and about
   twice as wide as the tortoise is long. Make the opening taller than you
   need now so it will fit for a while. The tray can be a simple cardboard
   tray lined with plastic. Make sure there are drain holes.
2. Put about 3cm (1 in) of good potting soil in the tray.
3. Cover the soil with a piece of galvanized mesh hardware cloth cut to the right size with the sharp bits cut or filed off, or bent over.
4. Optional but helpful- use nylon ties to secure waterproof soil warming cable to the hardware mesh. Be sure to leave enough cord to reach out of the habitat and follow manufacturer’s instructions.
5. Add another 3cm (1 in) of soil.
6. Sprinkle heavily with grass, forage plants, ground cover plants, etc. Seeds, sprouts, small rooted plants, or even sod or a preplanted ‘seed blanket’ may be used for this.
7. Provide appropriate water and light and let grow for 4-6 weeks.You can use a little safe fertilizer to help.
8. Carefully
   lift the plant and soil slab out of the tray, flex into a gentle arch,
   and set in place. Sculpt the substrate so the tortoise can easily get
   onto the new shelter to explore and graze.
9. Water and fertilize (lightly) as needed.

Combine the Moise Root Hide with the Bioactive Substrate for an incredibly naturalistic indoor habitat!

Other shelter ideas
Debris Piles
When
my heard of tortoises was in the outdoor pen one year, I decided to try
a ‘debris pile’ hide- I made a pile of branches, then covered it with
leaves, vines, and other natural ‘debris’ I found around the yard.

True Burrows
Easier
to do outside than indoors, many tortoises respond well to shelters
with real dirt around them. There are plans and ideas for this here, or this very helpful booklet about many aspects of tortoise care from the TortoiseGroup.org.

Heavy Plantings
Tortoises
often seek shelter under thick vegetation, wedged between woody stems,
etc. Putting several plants in one area offers a nice shelter. Ferns,
bromiliads, and other broadleaf plants work well for this. A tangle of
branches or roots can also be added to help young tortoises feel more
‘wedged in’.