The Shrine of the Bab on Mount Carmel in Haifa is illuminated at night, but the familiar golden dome is covered by a shroud while restoration work is under way. (Baha’i World Centre photo. All rights reserved.)

HAIFA, Israel — With great care and patience, a dozen trusted workers are going over the entire stone surface of Haifa's renowned Baha'i shrine, mending and cleaning every spot that shows damage from half a century exposed to the elements.

The stone restoration of the burial place of the Bab – one of two divine Messengers associated with the Baha'i Faith – is only one part of a four-year project that is bringing the benefits of 21st century engineering and building expertise to a structure whose first rooms were completed in 1909.

The initial phase of the work – structural reinforcement to increase resistance to earthquakes – began in 2008 and is virtually finished.

"A new concealed steel structure, masonry reinforcements, and concrete work are largely complete," said Saeid Samadi, architect and manager for the project. "The stone restoration should be finished by the end of the summer, and other work is well under way."

In addition to stonework and structural reinforcement, the painstaking restoration includes replacing the golden tiles on the dome, gilding anew the elements that feature gold leaf, replacing the red floor tiles inside the shrine, restoring the original ornamental balustrades, refurbishing the wood and metal doors and windows, installing new electrical and environmental control systems, and waterproofing.

The entire project is scheduled for completion in April 2012, but the exterior should be finished sooner, Mr. Samadi said. The refurbishing includes both the original one-story building that was completed a century ago and the outside colonnade, superstructure, and golden dome that were finished in 1953.

"The expectation is that by early October 2011, when the Baha'i pilgrimage season begins, visitors will be able to see the shrine in its full beauty and grandeur," Mr. Samadi said. "At the moment much of the exterior of the building is blocked from view."

In fact, extraordinary care has been taken to shield the restoration work from the public so that pilgrims and other visitors can continue to enter the shrine for prayer and also experience the beauty and peacefulness of the gardens.

Access to the tomb itself is suspended only during three summer months when no formal Baha'i pilgrimages are scheduled.

The Baha'i shrine on Mount Carmel is one of the most visited sites in the Holy Land. The building, overlooking Haifa Bay and the Mediterranean Sea, is known for its beauty and for the adjacent gardens that stretch up and down the mountain.

In 2008, the Shrine of Baha'u'llah north of Haifa, near Acre, and the Shrine of the Bab on Mount Carmel were chosen for the UNESCO World Heritage list, sites of "outstanding universal value" that should be considered part of the "cultural heritage of humanity."

The restoration work will not result in any change in the design or general appearance of the Shrine of the Bab.