My wife and I toured all of the San Antonio missions (a task even with road closures that takes only a little over half of the day). Remarkably, given that they were all built around the same time period, the missions are all different. We were also surprised by the ornate architectural details on some of the buildings, something expected in European cities but not on the Texas frontier. The Alamo, itself part of the Mission Trail, is by far the most important historically, but is probably the least interesting from an architectural standpoint. So if you've seen the Alamo, don't assume you've seen the typical Spanish mission.
Whatever the reason, the heat (95 plus degrees) may have kept people away, we had most of the missions to ourselves. Each, with the exception of the Alamo, is a working Catholic Church.
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