10 by sea

The city skyline recedes, waves pick up, a beer is cracked, and somewhere off the piers of Eastie, a seagull cries. You don’t have to hop a ferry to the Vineyard to fall under the spell of the sea. A reinvigorated seaport and new boat tours on Boston Harbor make this the best time in years to weigh anchor. Here are 10 ways to get your sea legs this summer without leaving the city.

1 JUST CRUISIN’

Flinging yourself out of bed before 10 a.m. on a weekend may be a challenge, but to see Boston at its most brilliant, catch the 9:30 a.m. architectural water tour out of Cambridge. As your peers are rubbing the sleep from their eyes, you’re riding a riverboat by MIT and Harvard and entering the Boston Harbor locks as a knowledgeable guide shares tales of the city’s most storied buildings. The Charles River Boat Company, Boston By Foot, and Boston Architectural Society partner up for this edifying foray. Ever wonder what it looks like under the Zakim Bridge? It’s more exciting than you think. Tours leave Mondays at 6 p.m. from the World Trade Center, $20, and Saturday and Sunday at 9:30 a.m. from the CambridgeSide Galleria, $25. www.charlesriverboat.com