San Diego’s public transportation gets a lively infusion of choreography with Trolley Dances this weekend.

Modern dance and San Diego’s public transportation system may seem like strange bedfellows, but when they come together in the annual Trolley Dances, now in its 14th year, the unusual combination works. Guests board the trolley in La Mesa and get off at six predetermined stops along the rail line; at each stop, some 50 adventurous dancers perform work choreographed specifically in response to the site. Organizers promise a “circus-like” atmosphere thanks to participating choreographers including Greg Sample (of So You Think You Can Dance and Cirque du Soleil fame) and French circus duo WillyGood. Held over two weekends, the event’s $30 admission price includes an all-day trolley pass; the two-hour tours leave on the hour between 10 am and 3 pm from Grossmont Transit Center, 8601 Fletcher Parkway, La Mesa. Sept. 29-30 and Oct. 6-7. 619.225.1803. sandiegodancetheater.org