Under the place Royale lie the remains of a massive palace first constructed in the 11th century, and upgraded over hundreds of years in line with the power and prestige of Brussels' successive rulers. Destroyed by a great fire in 1731, the palace was never reconstructed. Parts of the palace, and one or two of the streets that surrounded it, have been excavated and the underground site is a fascinating glimpse into Brussels' past. You can see the remains of palace rooms and walk up the steep cobbled rue Isabelle, once the busiest street in the city. Access is through the Musée BELvue.
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