Alsace is a whole region stretching from Strasbourg's cathedral to the Vosges wine villages, while Colmar is a single town inside it, often used as a base. Comparing them means choosing between roaming the region or settling into one walkable town.
Alsace is the whole province: Strasbourg's Cathédrale Notre-Dame de Strasbourg, the hilltop Château du Haut-Koenigsbourg, and Mulhouse's industrial museums all sit within one trip. Colmar is a single town within it, built around Maison Pfister, the House of Heads (Maison des Têtes), and the Koifhus (Old Customs House), all within a ten-minute walk.
Colmar's museum offering is essentially one stop: Musée Unterlinden, a genuinely excellent collection but a single destination. Alsace as a region adds two more heavyweight museums near Mulhouse, the Cité de l'Automobile - National Automobile Museum and the Cité du Train - Railway Museum, giving museum-focused travelers far more to see beyond Colmar.
Strasbourg's La Petite France is Alsace's best-known old quarter — canals, half-timbered houses, and a working-city backdrop. Colmar's La Petite Venise (Little Venice) is smaller and quieter, a few canal-side lanes rather than a full district, but it sits steps from Maison Pfister and the Koifhus (Old Customs House), making Colmar's center far more compact.
Both put you close to Eguisheim and Riquewihr, but the approach differs: Alsace as a region is typically toured via organized Alsace Wine Route Tours covering several villages at once. Colmar favors a Self-Guided Walking Tour of the town itself plus short trips to Eguisheim, Riquewihr, or Strasbourg.
Choose Alsace if you want the full spread — Strasbourg's cathedral, Haut-Koenigsbourg, and Mulhouse's museums alongside the wine villages. Choose Colmar if you want one compact, walkable base with Musée Unterlinden and easy day trips. Most itineraries end up combining both.