After touring southern Switzerland with Joseph Twichell, Sam joined his family at Lucerne and stayed at the Schweitzerhof Hotel.  He visited nearby towns and ascended the Rigi-Kulm.

See Bædeker Switzerland, 1879 page 41

Bædeker Switzerland (1877) Route 18 page 51

Basel has often been the site of peace negotiations and other international meetings. The Treaty of Basel (1499) ended the Swabian War. Two years later Basel joined the Swiss Confederation. The Peace of Basel in 1795 between the French Republic and Prussia and Spain ended the First Coalition against France during the French Revolutionary Wars. In more recent times, the World Zionist Organization held its first congress in Basel from 29 August through 31 August 1897.

Bædeker Belgium and Holland (1869) Route 13 page 139

The Acropolis of Athens (Greek: Ακρόπολη Αθηνών) is an ancient citadel located on a high rocky outcrop above the city of Athens and containing the remains of several ancient buildings of great architectural and historic significance, the most famous being the Parthenon. The word acropolis comes from the Greek words ἄκρον (akron, "edge, extremity") and πόλις (polis, "city").[1] Although there are many other acropoleis in Greece, the significance of the Acropolis of Athens is such that it is commonly known as "The Acropolis" without qualification.

From Bædeker's  The Rhine - 1873: pp 200-1

Stat. Achern (*Krone, or Post, carr, to Allerheiligen 7–8 fl.;*Adler, moderate; beer at Huber's and the Engel), a thriving little town, lies at the mouth of the Kappeler Thal. The market-place is adorned with a monument to the Grand Duke Leopold (d. 1852). In the vicinity is the admirably conducted Lunatic Asylum of Illenau, accommodating 400 patients. Hence through the Kappeler Thal to Allerheiligen.

Small town, mentioned by Bædeker, enroute between Venice and Florence 1867.  Known as Abano Bagni until 1924.   (Bædeker pp 221)

The Clemens' residence in Berlin, Germany from October 9, 1891 to New Years Eve, 1891

The Clemens' residence in Paris, France from November 16, 1894 to April 29, 1895, when they departed Europe to begin his world tour.