There is an architectural hajj, and now it is burdened with a time imperative. It is a journey all architects feel compelled to make at least once in their lifetime — to see the Kimbell Art Museum in Fort Worth. Until June 25, the Kimbell is hosting “Louis Kahn: The Power of Architecture.”

For its three-month run, expect to see even more architects and their associates circling the Kimbell in silent reverence because inside are Kahn’s drawings, models, videos, and photographs. It is an architectural rarity, a museum display of an architect’s preparatory work housed in one of the greatest buildings designed by the artist.

Filling half of the Kimbell’s Kahn-designed building is a collection of his work organized by the Vitra Design Museum of Weil am Rhein, Germany.

The exhibit opens with a 12-foot model of City Tower, a proposed project for Philadelphia, Kahn’s hometown. It was never built. Its large twisting helix shape influenced younger architects to imagine high rises as more than rectangular boxes. So the model was saved, and with an enormous photograph of the craggy-faced Kahn behind it, it sets the scene for the coming story about a man of small stature who left a huge imprint on his profession.

The galleries are filled with Kahn-related ephemera — his calendars that show constant travel broken only by his teaching commitments. There are letters, telegrams, his box of well-traveled pastels, as well as the expected framed architectural renderings and photographs.

It would be a mass of monochromatic pages from his life and practice were it not for his brilliant pastel sketches of landscapes and the occasional video screens that broadcast interviews with his contemporaries. This could not have been an easy exhibit to mount, yet Kimbell curator Jennifer Casler Price has done an excellent job staging the disparate objects around the models, which stand in for the completed projects.