Most popular Foursquare Tunnels in Chicago, USA

	Venue	Total check-ins	Total users	Tips	Check-ins per user
1.	'The Sky’s The Limit' Underground Walkway Tunnel btwn Concourse B and C (at ORD Airport)	7909	2506	23	3.16
2.	Hubbards Cave Tunnel Kennedy Expy	3889	551	3	7.06
3.	The Wormhole (It's a Shortcut) Tunnel	24	2	0	12.0
4.	Deep Tunnel Access Shaft Tunnel Hubbard St. Tunnel Access	21	4	1	5.25
5.	The Wells Street Dead-End Tunnel (Under the Roosevelt Bridge)	7	2	0	3.5
6.	The "Other" Tunnel Tunnel	7	5	0	1.4