We were standing at the top of the Sesame Streak, mom clutching a double inner tube, daughter hopping from one foot to the other with excitement, both of us dripping wet, when my 5-year-old made her annual query:

"Mommy, why can't we move to Sesame?"

Um, because I'd lose my mind?

Okay, okay, that is an overstatement. Or maybe not. Anyway, I got a reprieve: It was our turn at the top, and a few seconds later, we were whooshing down a water slide, slip-sliding through a tunnel and landing with a splash in the pool below. But her point had been made. "Sesame," as my daughter, Ryan, calls the Sesame Place water/amusement park outside Philadelphia, is a 5-year-old's idea of endless summer fun.

We are eager travelers, Ryan and I, backpacking through Costa Rica (she was so small she rode in the backpack, rather than wearing her own); swimming with dolphins in Mexico when Ryan was a toddler; taking spur-of-the-moment weekend adventures to Bermuda or the Bahamas. She has her own rolling suitcase, a cache of frequent-flier miles and an intimate knowledge of the local airports. She's even flown solo. Deep in her little-girl heart, though, few things (read: Disney World) top our annual two-day pilgrimage to Sesame Place, an easy drive to Langhorne, Pa., about 30 minutes north of Philadelphia. For Ryan, Sesame Place is about getting wet, getting thrilled and getting to see, live, the characters that have captivated her on television. It reveals, at heart, her secret 5-year-old life: She may have moved on to Mary-Kate and Ashley Olsen, abandoned her princess backpack for a sleek Adidas one and declared Dora the Explorer "a baby show," but she still harbors that early love of Elmo. Elmo plus water slides? Call it bliss.

Family trips like this one can either make the adult feel like a child again, or make the adult crazy. There are grown-ups who go to Disney World for their honeymoon, and grown-ups who go only because they feel it's required and wish the entire time that they were on a beach in Aruba. The former will do fine at Sesame, the latter likely will hate the place. Think lines, think noise, think overpriced and underwhelming food. Think about spending two days surrounded by everyone else's over-stimulated kids. While constantly wet.

In our case, though, the Aruba-loving mom has come to appreciate -- and, yes, even share -- the sheer happiness Sesame can bring a small person. We usually go sometime in late July or the thick of August, when the summer heat is at its worst and the idea of spending two days drenched by a water slide or dancing in a fountain has obvious appeal to kids and adults. This year, we moved the trip to late June, to celebrate the end of school.

Leaving the Washington area at 7 a.m. Saturday, we hit no traffic, pulling into the parking lot only a few minutes after the park opened at 10.

The first thing Ryan spotted was the roller coaster, which is designed to be entertaining for adults and bigger kids, but not so intense that it scares off the smaller ones. This produced our first dilemma of the day: Do we start with the coaster (which Ryan first tackled at age 4) or go straight to the water rides?

Given that it was over 85 degrees, the water won out.

Long ago liberated from the strollers that overrun the park, we rented a locker for our belongings and set out in swimsuits and swim shoes, with one towel to share and our essentials -- money for drinks and snacks and the locker key -- in a waterproof container.

First stop: Sky Splash, the giant raftlike tube ride that is crowned at the top of its six stories with an eight-foot-tall rubber duckie. We've learned from experience that this is the park's most popular attraction, and, like most kids (and grown-ups), Ryan can get tired of waiting in line. Early in the day, it's shorter, and we were down the big water slide within 20 minutes.

Once confined mainly to the wading pools, fountains and various stage shows ("Big Bird's Beach Party," with dancing characters; "Elmo's World Live!," which duplicates that portion of the "Sesame Street" television show), we had the run of the park now that Ryan is not only 5 but also a swimmer. We did the Slippery Slopes -- water slides without tubes or mats that doused us underwater at the bottom. We did Sesame Streak -- that double inner-tube ride through twists and tunnels -- a dozen times in a row. She used her own tube, instead of lap-riding, on Big Bird's Rambling River, and angled herself so she got completely drenched by the waterfalls overhead.

At 1:15, when folks started camping out along the parade route (parade at 2 p.m.), we got lunch, then claimed our little corner of the pavement to eat and wait. Parade character tally: handshake from Big Bird, handshake from Ernie, a picture taken with Zoe -- and a hug from Elmo (ka-ching!). We were in business.

After the parade came nine consecutive rides on the roller coaster (what a relief it doesn't go upside down); a visit to Oscar's Big Game Show, where Ryan was unhappily not selected to go onstage; ice cream and another half-dozen trips down Sesame Streak. Right before 6 p.m. -- fortunately before Ryan got wind that they repeat the parade at 6:30 -- we collected our stuff from the locker and headed for our hotel.

The Courtyard by Marriott Langhorne is just down the road from Sesame Place, and, consequently, is teeming with tired kids wearing wet bathing suits in the evening and overanxious kids wearing dry bathing suits in the morning. Hence, not a place to book if you've got business in Langhorne. But just fine for us. We showered, changed and headed out to dinner.

Most dinner options near Sesame Place fall into that unique American category we all know well: chain restaurants that are rife with crayons, coloring books, booster seats and kids' menus . . . but also hawk monstrously oversize drinks on multi-page laminated specialty cocktail menus. (Which, of course, remain permanently on the table, taunting you in your end-of-the-day desperation. Trust me, they know.) For those who are gluttons for punishment, the hotel offers directions to a local Chuck E. Cheese. Thankfully, when asked about nearby options, the front desk receptionist did not speak that evil by name.

I picked Chili's for no other reason than it was the first place we saw. We ate, we paid, we went back to the hotel, mom anticipating that her worn-out little bug would crash while she quietly channel-flipped, looking for a brain-dead movie so she could decompress. Alas, the clicker flipped by the Olympic gymnastic trials and a suddenly wide-awake girl squealed with joy. Call it the crowning moment in a sacrificial mommy day.

I always limit Day 2 to a half-day: We arrive at the park as it opens and depart immediately after the 2 o'clock parade, which gets us home just in time for dinner. We revisited our favorite water slide and the Oscar stage show (this time, Ryan thankfully was picked to play). I caved and let her play a handful of games in the carnival area (a total money vacuum) and let her select one souvenir.

By the time we left, I was relatively certain she was sated, our mini-adventure just long enough. Ha. Ten miles down I-95 and there it was again, the inevitable question:

"Mommy, why can't we move to Sesame?"

And this time I had 155 miles to formulate an answer.

Elmo and friends strut their stuff during the twice-daily parade at Sesame Place, just outside Philadelphia. At left, a boy soaks up the fun.