Off to Europe : Volumes From Card-Carrying Admirer of Oxford : More than a day-trip from London, the ancient university town rewards a longer stay.

With the ghosts of Oxford peering down from gray stone pinnacles and spires, I whispered the ancient oath:

“I hereby undertake not to remove from the Library, or to mark, deface, or injure in any way, any volume, document, or other object belonging to it or in its custody; not to bring into the Library or kindle therein any fire or flame, and not to smoke in the Library; and I promise to obey all rules of the Library.”

The guardian of the reader cards for the noble Bodleian Library smiled thinly, took my 5 note and issued me a pass--good for 12 days over the next five years.

(Mind you, I did not just wander in off the tangled, medieval streets and ask for a library card. With specific research in mind, I went armed with letters from United States professors who had Oxford University ties, and from friends who know I would not kindle anything--except in the hearth of my beloved mountain cabin near Julian, Calif.)

After crossing a flagstone courtyard and giving the security warden a crazed smile--in order to resemble the Polaroid photo on my reader pass--I climbed a worn staircase to the vast Duke Humfrey’s reading room, a vaulted-ceilinged repository for rare books and documents, and the oldest part of this library, founded in 1602.

Floor-to-ceiling shelves, crammed with fragrant, leather-bound books, lined the route. A small sign leaned near the entry stile: “All books printed before 1641 must be read on the premises.” That seemed fair.

*

After settling at a long oaken desk, rubbed by centuries of elbows, I looked across the aisle: A student was sound asleep on a foam-rubber book holder, his glasses askew on his nose, one arm hanging limp at his side.

A librarian spoke softly: “He’s not in for the fright he once would have had. We now test the fire-alarm system before the library opens, instead of at 12 noon.”

At day’s end, at the Kings Arms pub, I learned that a long history of devastating fires--especially the corker in 1190--have left both town and university skittish. That’s why slate is favored over thatch for roofing, someone said.

Another thing I did in Oxford that few Americans do: I stayed four days.

Too many travelers think of Oxford as a day trip from London, since it is only an hour northwest by car or train. They zip out at midmorning, peek into a college chapel and dining hall, browse the High Street, have lunch near the Sheldonian Theatre--designed by Christopher Wren--stare at the River Isis and then head back to London for dinner.

But the moody charms of the ancient university, and the town with which it is entwined, cannot be grasped in a few hours: Too many bells toll from too many towers; too many hidden gardens beckon beyond golden limestone walls; too many lakes with haughty swans are screened by chestnuts and willows.

A maze of a 1770s covered market--these days selling oddments from marmalades to haggis to hand-knit sweaters--lurks down a narrow lane, just steps from the Mitre pub. The cavernous Blackwell bookshop is as tempting an exploration as punting on the River Cherwell, pushing off from Magdalen Bridge.

Each of the 36 colleges is different in size and shape, in tradition and wealth and manner. They fit together like a jigsaw puzzle that has been dropped, broken and somehow pressed back together so that it is almost right: Walls dead-end at taller walls; creaking wooden gates lead to grassy quads and meadows and playing fields. Lacy stone spires shimmer over every block, vying for height and splendor.

Three colleges claim to be the oldest: Balliol, Merton and University were all founded in the 1200s. The longest and best preserved stretch of old City Wall looms alongside New College, which was founded in 1379.

I have endless reasons to go back to Oxford--museums and college galleries I have not seen, choirs and concerts I have not heard, footpaths I have not wandered. Above all, it’s a practical matter: I still have a week on my library card.