It was a milestone week for several downtown Minneapolis construction projects.

On Tuesday morning, crews set the highest beam on the two 17-story towers being built near the new Vikings Stadium for Wells Fargo. On Wednesday, Sherman Associates hosted an official groundbreaking ceremony at its Encore rental apartment project near the Guthrie Theater in the Mill District. And Mortenson Construction, which has nearly 1,000 workers building the stadium, hosted a topping off celebration on the incomplete 30th-floor amenity deck of its 4Marq apartment tower at the corner of Marquette Avenue and S. 4th Street in Minneapolis.

The building is one of several luxury apartment towers to open recently in the Central Business District, including the neighboring Nic on Fifth apartments, which were built and recently sold by Opus, and the Soo Line Apartments, which were carved out of a converted historic office building by Michigan-based Village Green.

In front of an audience in hard hats and fluorescent yellow vests that included City Council Members Jacob Frey and Lisa Goodman, Mortenson senior vice president Ken Sorensen praised the workers who have managed to keep the project on schedule by pouring a new concrete floor every four days.

"We are building a world-class city," said Sorensen.

The 260-unit building will have mostly studio and one-bedroom apartments, but there will also be several three-bedroom units. Crews are already putting the finishing touches on the eighth-floor units, and are working their way up. The first several floors of the building contain parking.

Mortenson's general manager, Bob Solfelt, said that even though leasing won't begin until this summer, one of the units had already been spoken for. Rents haven't been set yet, but the company will soon be opening a skyway level sales center. The building, which was designed by UrbanWorks Architecture in Minneapolis, will be managed by Lincoln Properties.

Mortenson sold the 4Marq apartment project to its capital partner, American International Group Inc.

Also this week, Mortenson closed on the purchase of a parking lot at 401 Hennepin Av. S., where it plans to build the metro's first Hotel AC by Marriott, which will cater to travelers looking for a more European-style boutique hotel experience. Mortenson paid $4.8 million for the site, according to property records. Construction on the 244-room hotel is expected to begin soon.

And one other construction project topped off on Thursday: the new, nine-story headquarters for Xcel Energy.

Jim Buchta