Whether or not it was the place in which that baby gymnast strangled the serpents who sought to kill him in his cradle, it is indeed ancient enough to suit any boy or girl who likes to dig among the relics of the past. For more than eight centuries the same granite walls that now surround it have lifted their gray ramparts out of the vast and granite-covered plains that make the country so wild and lonesome, while its eighty-six towers and gateways, still unbroken and complete, tell of its strength and importance in those far-off days, when the Cross was battling with the Crescent, and Christian Spain, step by step, was forcing Mohammedan Spain back to the blue Mediterranean and the arid wastes of Africa, from which, centuries before, the followers of the Arabian Prophet had come.

At the time of our story, in the year 1525, this forcing process was about over. Under the relentless measures of Ferdinand and Isabella, with whose story all American children, at least, should be familiar, the last Moorish stronghold had fallen, in the very year in which Columbus discovered America, and Spain, from the Pyrenees to the Straits of Gibraltar, acknowledged the mastership of its Christian sovereigns.

But the centuries of warfare that had made the Spaniards a fierce and warlike race, had also filled Spain with frowning castles and embattled towns. And such an embattled town was this same city of Avila, in which, in 1525, lived the stern and pious old grandee, Don Alphonso Sanchez de Cepeda, his sentimental and romance-loving wife, the Donna Beatrix, and their twelve sturdy and healthy children.

Religious warfare, as it is the most bitter and relentless of strifes, is also the most brutal. It turns the natures of men and women into quite a different channel from the one in which the truths they are fighting for would seek to lead them; and of all relentless and brutal religious wars, few have been more bitter than the one that for fully five hundred years had wasted the land of Spain.

To battle for the Cross, to gain renown in fights against the Infidels—as the Moors were then called,—to "obtain martyrdom" among the followers of Mohammed—these were reckoned by the Christians of crusading days as the highest honor that life could bring or death bestow. It is no wonder, therefore, that in a family, the father of which had been himself a fighter of Infidels, and the mother a reader and dreamer of all the romantic stories that such conflicts create, the children also should be full of that spirit of hatred toward a conquered foe that came from so bitter and long-continuing a warfare.

Don Alphonso's religion had little in it of cheerfulness and love. It was of the stern and pitiless kind that called for sacrifice and penance, and all those uncomfortable and unnecessary forms by which too many good people, even in this more enlightened day, think to ease their troubled consciences, or to satisfy the fancied demands of the Good Father, who really requires none of these foolish and most unpleasant self-punishments.

But such a belief was the rule in Don Alphonso's day, and when it could lay so strong a hold upon grown men and women, it would, of course, be likely to work in peculiar ways with thoughtful and conscientious children, who, understanding little of the real meaning of sacrifice and penance, felt it their duty to do something as proof of their belief.

So it came about that little ten-year-old Theresa, one of the numerous girls of the Cepeda family, thought as deeply of these things as her small mind was capable. She was of a peculiarly sympathetic, romantic, and conscientious nature, and she felt it her duty to do something to show her devotion to the faith for which her father had fought so valiantly, and which the nuns and priests, who were her teachers, so vigorously impressed upon her.

She had been taught that alike the punishment or the glory that must follow her life on earth were to last forever. Forever! this was a word that even a thoughtful little maiden like Theresa could not comprehend. So she sought her mother.

"Forever? how long is forever, mother mine?" she asked.

But the Donna Beatrix was just then too deeply interested in the tragic story of the two lovers, Calixto and Melibea, in the Senor Fernando de Rojas' tear-compelling story, to be able to enter into the discussion of so deep a question.

"Forever," she said, looking up from the thick and crabbed black-letter pages, "why forever is forever, child—always. Pray do not trouble me with such questions; just as I am in the midst of this beautiful death-scene too."

The little girl found she could gain no knowledge from this source, and she feared to question her stern and bigoted old father. So she sought her favorite brother Pedro—a bright little fellow of seven, who adored and thoroughly believed in his sister Theresa.

To Pedro, then, Theresa confided her belief that, if forever was so long a time as "always," it would be most unpleasant to suffer "always," if by any chance they should do any thing wrong. It would be far better, so argued this little logician, to die now and end the problem, than to live and run so great a risk. She told him, too, that, as they knew from their mother's tales, the most beautiful, the most glorious way to die was as a martyr among the infidel Moors. So she proposed to Pedro that she and he should not say a word to any one, but just start off at once as crusaders on their own accounts, and lose their lives but save their souls as martyrs among the Moors.

The suggestion had all the effect of novelty to the little Pedro, and while he did not altogether relish the idea of losing his life among the Moors, still the possibility of a change presented itself with all the attractions that the thought of trying something new always has for children. Besides, he had great respect for his sister's judgment.

"Well, let us be crusaders," he said, "and perhaps we need not be martyrs, sister. I don't think that would be so very pleasant, do you? Who knows; perhaps we may be victorious crusaders and conquer the Infidels just as did Ruy Diaz the Cid. See here, Theresa; I have my sword and you can take your cross, and we can have such a nice crusade, and may be the infidel Moors will run away from us just as they did from the Cid and leave us their cities and their gold and treasure? Don't you remember what mother read us, how the Cid won Castelon, with its silver and its gold?"

And the little fellow spouted most valiantly this portion of the famous poem of the exploits of the Cid (the Poema del Cid), with the martial spirit of which stirring rhyme his romantic mother had filled her children:

Theresa applauded her little brother's eloquent recitation, and thought him a very smart boy; but she said rather sadly: "I fear me it will not be that way, my Pedro; for martyrdom means, as mother has told us, the giving up of our life rather than bow to the false faith of the Infidel, and thus to save our souls and have a crown of glory."

"The crown would be very nice, I suppose, sister," said practical young Pedro, "especially if it was all so fine as the one they say the young King Carlos wears—Emperor, too, now, is he not? Could we be emperors, too, sister, if we were martyrs, and had each a crown? But we must be crusaders first, I suppose. Come, let us go at once."

The road from granite-walled Avila to the south is across a wild and desolate waste, frowned down upon on either hand by the savage crests of the grim sierras of the Guadarrama. It winds along gorges and ravines and rocky river-beds, and has always been, even in the days of Spanish power and glory, about as untamed and savagely picturesque a road as one could well imagine.

Along this hard and desolate road, only a few days after their determination had been reached, to start upon a crusade the brother and sister plodded. Theresa carried her crucifix, and Pedro his toy sword, while in a little wallet at his side were a few bits of food taken from the home larder. This stock of food had, of course, been taken without the knowledge of the mother, who knew nothing of their crusade, and this, therefore, furnished for Theresa another sin, for which she must do penance, and another reason for the desired martyrdom.

They had really only proceeded a few miles into the mountains beyond Avila, but already their sturdy little legs were tired, and their stout little backs were sore. Pedro thought crusading not such very great fun after all; be was always hungry and thirsty, and Theresa would only let him take a bite once in a while.

"Don't you suppose there is a Moorish castle somewhere around here that we could capture, and so get plenty to eat?" he inquired of his sister. "That is what the Cid was always finding. Don't you remember how nicely he got into Alcacer and slew eleven Infidel knights, and found ever so much gold and things to eat? This is what he said, you know:

"O Pedro, dear, why will you think so much of things to eat," groaned Theresa. "Do you not know that to be hungry is one way to be a martyr. And besides, it is, I doubt not, our just punishment for having taken any thing to eat without letting mother know. We must suffer and be strong, little brother."

"That's just like a girl," cried Pedro, a trifle scornfully. "How can we be strong if we suffer? I can't, I know."

But before Theresa could enter upon an explanation of this most difficult problem—one that has troubled many older heads than little Pedro's,—both the children started in surprise, and then involuntarily shrunk closer to the dark gray rock in whose shadow they were resting. For there, not a hundred yards distant, coming around a turn in the road, was one of the very Infidels they had come out to meet and conquer, or be martyred by.

He was a rather imposing-looking but not a formidable old man. His cloak or mantle of brown stuff was worn and ragged, his turban was quite as dingy, but the long white beard that fell upon his breast made his swarthy face look even fiercer than it really was, and the stout staff, with which he helped himself over the uneven road, seemed to the little crusaders some terrible weapon of torture and of martyrdom.

But Pedro was a valiant little fellow after all. The fighting spirit of his father the Don burned within him, and few little folks of seven know what caution is. He whispered to his sister, whose hand he had at first clutched in terror, a word of assurance.

"Be not afraid, sister mine," he said. "Yonder comes the Infidel we have gone forth to find. Do you suppose he has a whole great army following him? Hold up your crucifix, and I will strike him with my sword. The castle can't be far away, and perhaps we can conquer this old Infidel and find a good dinner in his castle. That 's just what the Cid would have done. You know what he said:

Let us battle with him at once."