Hard to believe, but Upstairs On The Square (91 Winthrop Street, Cambridge) is celebrating five years in its current location — and a whopping 25 years in Harvard Square. On July 12, help the restaurant kick off a full schedule of summer activities and toast their recent renovations with a Grand Reopening Party, beginning at 6 pm. The cost is $25 and includes a rum punch or other cocktail, hors d’oeuvres, and small plates; the event also features live music and dancing. Call 617.864.1933 for information.