Barcelona is an architectural treasure trove. Everywhere we turn, we find beautiful buildings, truly gems of artistic design and craftsmanship. The amazing part is the abundance of it. Most big cities have some nice buildings, but in Barcelona, they are everywhere. Most of them were built in the last several centuries, but many are relatively recent. The wealth generated by the Industrial Revolution, combined with Spain's expertise in metal and stone works, were put into good use. The city held an open house during a weekend for many such buildings, called a "48 Hour Open House", and we were fortunate to be able to get into a few of these buildings.