Something strange is happening on the Capital Beltway and at the infamous Springfield Mixing Bowl. Something so strange that most people say they've never quite seen anything like it.

Traffic is zooming -- even during rush hour. Merging in the Mixing Bowl is safer and smoother. Blood pressure levels are down. Productivity is up.

The catalyst of this most unfamiliar development is a new, mile-long ramp that links the inner loop of the Beltway to the southbound lanes of Interstate 95, carrying drivers up and over the tangle of the Mixing Bowl in the process.

The ramp replaces the old setup that forced drivers to exit the inner loop and merge into the heart of the Mixing Bowl to get onto I-95. The magic of the ramp isn't so much that it has turned I-95 into a fast-flowing freeway -- at 5 p.m. Monday, cars and trucks were backed up from the base of the ramp across its whole length and on south down the highway to the far reaches of Washington's suburbs.

But with the shift of about 20,000 motorists a day onto the ramp and off the inner loop, where traffic used to grind to a halt behind the exit, the Beltway is no longer a multi-mile parking lot each afternoon and evening. At the same time cars were backed up on the ramp Monday, traffic flew through on the Beltway at 65 mph and faster. And by swinging drivers over and beyond the interchange, the ramp has removed those 20,000 vehicles from the Mixing Bowl.

That gives drivers coming from the outer loop and I-395 an easier ride. This is all a very positive, if a little perplexing, development for motorists.

"There's been a noticeable change," said Humphrey Mensa, pumping gas about 5:30 p.m. Monday after his regular journey through the Mixing Bowl. "I didn't have anyone cut in front of me. That's strange."

The hardened Mixing Bowl veteran that he is, Mensa said the easier ride, reduced tension and safer journey left him feeling a little freaked out. "I thought, 'Well, nobody is cutting in front of me,' " he said. "I thought, 'What is going on?' "

Sure, it's only been a week that the ramp has been open and things can change quickly on the region's highways, but what is going on is that the $31 million ramp is the first piece of the eight-year Mixing Bowl construction puzzle to address one of the dangerous merges of the Beltway, I-95 and I-395. The first five years of the nearly $700 million project focused mostly on roads that feed into the interstates.

"It took me aback to see such a radical, almost revolutionary, change in traffic," said Fairfax County Supervisor Gerald W. Hyland (D-Mount Vernon), after passing through the area last week. "I've been calling it a transportation laxative."

Over the next three years, several similar ramps designed to loosen the knot caused by the convergence of 430,000 cars and trucks each day will open. By the end of next year, a ramp connecting the northbound lanes of I-95 to the outer loop of the Beltway is scheduled to become operational. Several major ramps and bridges connecting I-95 and the Beltway west of the interchange, as well as reconfigured lanes on I-95 and I-395, are slated to open in early 2006.

Alas, construction on those ramps and bridges is going to return parts of the area to the more familiar scene of bumper-to-bumper backups by summer's end, project officials said.

All of the northbound lanes of I-95 south of the Beltway will be closed for construction work on bridges connecting the interstate to the inner and outer loops, project spokesman Steve Titunik said. If possible, that work will be done late on Saturday nights, when traffic is lightest, Titunik said. Titunik also said construction of connectors between I-395 and the outer loop will cause lane closures on the Beltway.

"Without question, there's going to be [traffic] interruptions," Titunik said.

One problem on the new ramp is that two lanes merge at its end, causing some delays as cars and trucks move onto southbound I-95. That should be better by the end of the year, when both lanes empty directly onto I-95, project officials said. Nonetheless, they're pleased that the new ramp is making a difference and that no major accidents have occurred as drivers adjust.

That goes double for Cate Pederson, who was anxious about the new setup hours before she took the ramp for the first time last week. "I even called my husband as I approached the ramp and said, 'Here we go,' " she recalled. "I was on it at 6:30 that evening, and it was an absolutely beautiful ride. I made it through the interchange in less than three minutes. It usually takes 10 to 15 minutes."

Since then, Pederson said, traffic has been a little spottier, with cars backing up on the ramp some days. But even this is better than the way it used to be, she said. Backing up on the ramp "allows you to be more patient and stay in place rather than worry about getting over" to exit onto I-95, she said.

Longtime WTOP traffic reporter Bob Marbourg said the improvements are "dramatic."

"We got our $31 million worth," Marbourg said. "It seems to be doing exactly what it's supposed to do, separating through travelers from local traffic and eliminating much of the weaving that was taking place. This one change has really made a striking difference."

At 4:30 p.m., traffic from the Capital Beltway's inner loop rides above the Mixing Bowl to join I-95 toward Richmond.

As rush hour starts, the ramp, center, delivers southbound traffic from the inner loop to join cars and trucks from the outer loop and Interstate 395, left.