On our recent trip to Wales, a two-and-a-half-hour drive from Pembrokeshire brought us to the inconspicuous gateway of Ynyshir Hall. There, the grounds were just as we remembered, with majestic trees set in expansive, gently sloping lawns. The two-story house is a surprisingly modest structure, particularly as one of its former owners was Queen Victoria, who planted a Persian ironwood tree that more than a century later is still renowned for its splendid fall foliage.