The Royal Greenhouses in Laeken, Belgium (near Brussels), are open to the public for just three weeks. If you want to wander the six acres of neoclassical rotundas, domes and galleries, you need to get there between April 15 and May 9, 2010. Twenty full time gardeners tend the giant ferns, fruit-bearing banana trees, grottoes, glades and grassy vistas of the greenhouses. Highlights include the Azalea House, the rotunda, a colony of birds and the orange trees. Walkways are filled with climbing geraniums and fuchsias, whose blossoms form an overhead canopy. The visit ends with a short walk through the Royal Park. Besides the greenhouses, the visit includes the Queen Elisabeth’s workshop and castle’s stables, which were built in the beginning of the 20th century during the reign of King Leopold II and King Albert I.

Hours on Tuesdays, Wednesdays and Thursdays are 9:30 a.m. to 4 p,m. On Fridays, the greenhouses will be open from 1-4 p.m. and again from 8-10 p.m. On Saturdays and Sundays, opening hours are 9:30 a.m. to 4 p.m. and 8-10:00 p.m. (Yes, the greenhouses will not be open on Mondays, and admission on April 20 is reserved for visitors with disabilities. Admission fee is 2.50 euro, but visitors under the age of 18 are admitted for free.