One will often try and abandon several caves or partially dug-out burrows in succession before finding a place to its taste.

It always endeavors to choose a spot where there is little chance of discovery or molestation, taking great care to avoid leaving too evident trace of its work.

Hence it is not often that the dens are found.
Once in its den the bear passes the cold months in lethargic sleep; yet, in all but the coldest weather, and sometimes even then, its slumber is but light, and if disturbed it will promptly leave its den, prepared for fight or flight as the occasion may require.

Many times when a hunter has stumbled on the winter resting-place of a bear and has left it, as he thought, without his presence being discovered, he has returned only to find that the crafty old fellow was aware of the danger all the time, and sneaked off as soon as the coast was clear.

But in very cold weather hibernating bears can hardly be wakened from their torpid lethargy.
The length of time a bear stays in its den depends of course upon the severity of the season and the latitude and altitude of the country.