Travel from Coventry to heathrow

I wouldn't want to be that far from Heathrow the night before my flight. I'm conservative about such things, because the thought of having to take (pay for) a taxi over that distance if something went wrong makes me twitch.

I have twice stayed at the fairly new and extremely economical Premier Inn near Heathrow Terminal 4. It's about a 15-minute walk from the terminal through an enclosed walkway. You can probably get a very good rate there; I always have. Do be careful to note whether you're booking the non-refundable rate or the flex rate.

As of about a week ago the website was still messing up the arrival date input by the prospective visitor. Either use the Premier Inn app on you phone or tablet or be very, very careful to assure that the arrival date you want sticks around through the entire booking process. I found it necessary to get to the webpage for the specific PI hotel, then indicate I wanted to search again; usually that worked and I could book the night I wanted. Fortunately, the company is better at running hotels that it is in maintaining a good website.

Do you think it is necessary to book ahead, or could I simply arrive and get a room?

Although I am not guaranteeing anything, I have a strong suspicion you'd be able to get a room if you just walked in. I wouldn't normally say that, but if a newish hotel that is perfectly nice and located at a major airport has refundable single room rates (even though booked in advance) often in the 50- to 60-pound range, it's hard to imagine that its occupancy rate is super high.

On the other hand, Premier Inn's policy on its flexible rates is that you can cancel for free until 1 PM on the scheduled day of arrival, so what do you have to lose? Other than the annoyance of having to deal with the ever-changing-arrival-date problem on the PI web site, I don't see any reason not to go ahead and book a room. The flexible rate does tend to creep up as you get closer to the arrival date.

Is there a need to book train tickets ahead of time?

You will need to be at Heathrow at 8am, so you definitely need to be there the night before, so book your hotel now. Rail fares don’t seem to be any cheaper booking 11 weeks out, so buy on the day.

Do trains ever sell out? and do you prefer coach or train?

Trains are usually faster unless you have to make a connection somewhere with a significant layover and you have an option of a direct bus/coach. And you're more likely to run into delays on a bus because of unpredictable traffic.

I have no problem at all with buses and often will choose that option if it is noticeably cheaper (which is not rare). It depends on how tight my time is. A side benefit of buses is that it's a lot easier to roll your suitcase to the side of the bus and lift it 12" to 18" off the ground to place it in the hold than to maneuver your suitcase up the narrow steps onto a train and hope there will be a spot left on the luggage rack.

Trains never sell out.

I would take a coach - there are several each day direct from Coventry to Heathrow, so avoiding London.

https://www.nationalexpress.com/en

Can you advise about safety for a female travel alone from Heathrow to Cambridge, around 11pm?

why would you be asking about safety in England - it doesn't make sense. Do you come from an unsafe country?

Can you advise about safety for a female travel alone from Heathrow to Cambridge, around 11pm?

Yes, use your common sense.

Coaches are better than trains for getting to Heathrow if you are somewhere reasonably close to London like Coventry, as you don't need to make multiple changes in central London.

unless you need to be at the airport by 8, which means London bound rush hour traffic in the height of the peak from Coventry on the M1 or M40 (I don't know which they use because I don't know where else they stop on the way).