It's not uncommon for a line to form outside the Starbucks Reserve Roastery in Shanghai on weekends, and even on weekday nights.

Donning a suit and tie, with an earpiece in his ear, a security guard stands outside the world's largest Starbucks — which, given its hip exterior, could easily be mistaken for a nightclub.

There may be another standalone Starbucks coffee shop right across the street, but the customers waiting in line aren't here just for a caffeine fix.

For them, it's about hanging out inside the largest Starbucks in the world, which offers a high-end experience in a flashy building spanning nearly 30,000 square feet. It even has an in-house map, which looks very much like the something for an amusement park.

There are only two Starbucks Reserve Roastery outlets in the world: one in Shanghai and the other in Seattle where the company is headquartered. The coffee giant already has plans to open more outlets globally in locations such as Milan, Tokyo, New York and Chicago.

The Shanghai superstore, which opened in December 2017, features its own roasting facility and hand-crafted coffee bars. It has new offerings — such as nitro draft lattes and alcoholic drinks — which are not found in normal Starbucks outlets.

It is also home to the innovation center where new concoctions such as beer infused with coffee are created.

The food there is prepared by Starbucks strategic partner Princi Café — a Milan-based cafe that offers pastries, pizza and alcoholic drinks.

Inside the Shanghai store, staff members go around taking orders with their tablets instead of customers lining up behind the counter to make their purchases.

But be prepared. Items aren't cheap here: One serving of a pizza square can cost 78 yuan, or about $11.40.