Thirty-some years ago, it was simply the best fort a kid could ask for, an iron tower where the most innocuous thwack of a stick sword would resonate through your very bones. Climb to the top, and marauders could be spotted miles away.

But now that the decorum of adulthood (and better barriers) prevents me from sneaking in, I have to limit my visits to the Netherlands Carillon to regular opening hours.

Located near the Iwo Jima Memorial in Arlington (on Marshall Drive, between Route 50 and Arlington National Cemetery), this bell tower, this gift from the Netherlands to the people of the United States, is sadly overlooked by most locals. Which means they'll miss one of the best ways to spend a Saturday afternoon I know: Through September, the carillon plays its heart out in free concerts each Saturday from 2 to 4 p.m. The broad lawn and vibrant flower beds around the carillon make a perfect picnic spot for a unique concert. But now, as in childhood, the best part is still the climb to the top.

The first level is reached by a dizzying long climb up the iron steps. You pass within feet of the bells, which range in size from minivan to toaster oven and can make your fillings ring. The final level, reached only by a narrow winding staircase, offers exceptional panoramic views of the Mall, as well a chance to watch the carilloneur at work. The bells are played from a keyboard of wooden rods and pedals, in a physically demanding musical performance. Fortunately, they installed air conditioning in the glass booth during recent renovations.

For information, call 703- 289-2530.

--Victoria McKernan, Washington

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