The closest subway stops to Penn Station at 234 W 31st St in New York City are:
1. 34th Street - Penn Station (served by the 1, 2, 3, A, C, E lines): This is the most convenient subway stop, located right at Penn Station. It provides easy access to many popular destinations in Manhattan.
2. 34th Street - Herald Square (served by the B, D, F, M, N, Q, R, W lines): Located just a short walk from Penn Station, this stop is perfect for exploring the bustling Herald Square area, home to the iconic Macy's department store.
In terms of recommendations, there are plenty of things to do and see near Penn Station. Here are a few suggestions:
1. Empire State Building: One of the most famous landmarks in New York City, the Empire State Building offers stunning views of the city from its observation deck. It's just a short walk from Penn Station. [Empire State Building](https://www.esbnyc.com/)
2. Madison Square Garden: If you're a sports fan or interested in catching a live concert, Madison Square Garden is a must-visit. This iconic venue hosts a variety of events throughout the year. [Madison Square Garden](https://www.msg.com/madison-square-garden)
3. High Line: Take a leisurely stroll along the High Line, an elevated park built on a historic freight rail line. It offers beautiful views of the city and is a great place to relax and enjoy some greenery. [The High Line](https://www.thehighline.org/)
4. Times Square: Just a few subway stops away from Penn Station, Times Square is a vibrant and bustling area known for its bright lights, Broadway shows, and endless entertainment options. [Times Square](https://www.timessquarenyc.org/)
Remember to check the MTA website for any subway updates or service changes before your visit. You can find the latest information at [MTA Subway Service Updates](http://www.mta.info/). Enjoy your time in New York City!