What visitors really come to Middleton Place to see are its impressive series of geometric gardens laid out in the 18th century, a landscape that the Garden Club of America once called the nation's most important.

But increasingly, Middleton's built landscape has become more worthy of attention, too.

The Inn at Middleton Place, designed by architect W.G. Clark more than 30 years ago, can be considered one of the Lowcounty's architectural triumphs of the late 20th century.

Meanwhile, smaller projects have made their own mark here, from Clark's simple portal into the historic gardens to architect Randolph Martz's tiered expansion of the dining room and now Middleton's new pavilion, an event space designed by architect Reggie Gibson.

The pavilion is the most recent addition, one that replaces a smaller and much more background structure where Middleton can host weddings, large meetings and similar events. At least most of it was replaced: Gibson's design incorporates a rectangular portion of the old pavilion that has kitchen space and restrooms: It's the less visible, utilitarian part of the T-shaped structure.

The trunk of the "T" is what's meant to catch one's eye.

It's sited at the southwestern edge of the greensward, the enormous lawn between the highway and the site where the Middleton mansion once stood and where a surviving flanker still stands.

The architecture juggles two goals: being an attractive, intriguing building worthy of the landscape but not drawing too much attention away from its surroundings, which include not only the greensward and house ruins, but also the distant gardens and work spaces.

"We wanted you to come into a beautiful comfortable space but not forget you're at Middleton Place," Middleton's new CEO Tracey Todd says. "That was Reggie's mandate, and I think he nailed it."

The pavilion recently was finished by Southeastern Construction of Summerville and opened its doors in late spring.

Among the most dramatic touches are the pavilion's three white portals: one facing east and two facing north. They're nearly identical to Clark's single black (or Charleston green?) portal through which visitors pass from the parking lot into the gardens.

All four portals seems like a modern, spare riff on torii, traditional Japanese gates often built at the entrance to a shrine, where they signify the transition from the secular to the sacred.

The other standout piece is the main oak doors, which were milled from pieces of the Middleton Oak, which lost a massive branch a decade ago. (This tree is one of two oaks at Middleton that are larger around than the Angel Oak on Johns Island).

On the inside, the pavilion's approximately 13-foot ceilings and ample windows give those inside a sense they're somewhere nice. Sections of wall and ceiling are reclaimed fencing reclaimed from a Kentucky horse farm, then whitewashed, a sort of an elegant, rustic touch, if that's not too much of an oxymoron.

The northeastern corner is curved, a detail suggested by a Middleton trustee and one that accentuates the best view. The building's upper third still meets at a right angle and is supported by a thin column, not unlike a traditional Charleston corner store.

But much of the design is done to help the building simply blend in. Few will notice that the new addition comes out at a slight angle to avoid losing a large branch from a nearby oak, but it does.

The most ornate touch is reserved for the entrance hall, where a large sculptural light fixture dominates. The unique piece, fabricated by North Charleston ironworker Robert Thomas, was inspired by the branches of a live oak.

But it's not too literal, says Thomas, who also made custom door handles for the Middleton Oak door.

The building's dark green cladding gives it a subdued hue much like the previous pavilion. And that suits Charles Duell, who recently retired as Middleton's President and CEO after almost a half century transforming it. The pavilion serves as one of the final major projects he has brought about, and it's fitting that the pavilion tries to do what he has done: keep Middleton rooted in its history while also making it better.

"It really melds into the live oaks very successfully," Duell says. "It's not an architectural monument, which we don't want it to be."

That's only fitting, given that the main monument here will always be the gardens.

Reach Robert Behre at 843-937-5771. Follow him on Twitter @RobertFBehre.