Boston’s latest spate of hotels has hopped the Charles River, leaving the city behind for cerebral Cambridge. THE KENDALL refashions a Victorian-age fire department station house into a 65-room boutique hotel — 11 rooms in the original brick building and the balance in a built-to-match addition, all with Americana decor and reproduction antiques. From $129. (617) 577-1300, A grand fireplace in the lobby surrounded by cozy couches and animal-print pillows introduces guests to the convivial HOTEL MARLOWE, a 236-roomer with stylized nautical looks and a bustling brasserie. From $159. (800) 825-7040,